diff --git a/stella/src/common/mainSDL.cxx b/stella/src/common/mainSDL.cxx
index 517c7a528..87d67cbbd 100644
--- a/stella/src/common/mainSDL.cxx
+++ b/stella/src/common/mainSDL.cxx
@@ -13,7 +13,7 @@
 // See the file "license" for information on usage and redistribution of
 // this file, and for a DISCLAIMER OF ALL WARRANTIES.
 //
-// $Id: mainSDL.cxx,v 1.45 2005-06-16 16:36:48 urchlay Exp $
+// $Id: mainSDL.cxx,v 1.46 2005-06-17 14:42:48 stephena Exp $
 //============================================================================
 
 #include <fstream>
@@ -152,7 +152,8 @@ int main(int argc, char* argv[])
   }
 
   // Request that the SDL window be centered, if possible
-  //	putenv("SDL_VIDEO_CENTERED=1");
+  if(theOSystem->settings().getBool("center"))
+    putenv("SDL_VIDEO_CENTERED=1");
 
   // Create the framebuffer(s)
   if(!theOSystem->createFrameBuffer())
diff --git a/stella/src/debugger/Debugger.hxx b/stella/src/debugger/Debugger.hxx
index e630c2842..669c73bf8 100644
--- a/stella/src/debugger/Debugger.hxx
+++ b/stella/src/debugger/Debugger.hxx
@@ -13,7 +13,7 @@
 // See the file "license" for information on usage and redistribution of
 // this file, and for a DISCLAIMER OF ALL WARRANTIES.
 //
-// $Id: Debugger.hxx,v 1.9 2005-06-17 03:49:08 urchlay Exp $
+// $Id: Debugger.hxx,v 1.10 2005-06-17 14:42:49 stephena Exp $
 //============================================================================
 
 #ifndef DEBUGGER_HXX
@@ -49,7 +49,7 @@ enum {
   for all debugging operations in Stella (parser, 6502 debugger, etc).
 
   @author  Stephen Anthony
-  @version $Id: Debugger.hxx,v 1.9 2005-06-17 03:49:08 urchlay Exp $
+  @version $Id: Debugger.hxx,v 1.10 2005-06-17 14:42:49 stephena Exp $
 */
 class Debugger : public DialogContainer
 {
@@ -95,6 +95,10 @@ class Debugger : public DialogContainer
       sprintf(out, "%04x", i);
       return out;
     }
+    static int hex_to_dec(const char* h)
+    {
+      return (int) strtoimax(h, NULL, 16);
+    }
 
     void toggleBreakPoint(int bp);
     bool breakPoint(int bp);
diff --git a/stella/src/emucore/Settings.cxx b/stella/src/emucore/Settings.cxx
index 8ad22bc5d..cd14fea82 100644
--- a/stella/src/emucore/Settings.cxx
+++ b/stella/src/emucore/Settings.cxx
@@ -13,7 +13,7 @@
 // See the file "license" for information on usage and redistribution of
 // this file, and for a DISCLAIMER OF ALL WARRANTIES.
 //
-// $Id: Settings.cxx,v 1.48 2005-06-16 01:11:28 stephena Exp $
+// $Id: Settings.cxx,v 1.49 2005-06-17 14:42:49 stephena Exp $
 //============================================================================
 
 #include <cassert>
@@ -48,6 +48,7 @@ Settings::Settings(OSystem* osystem)
   set("zoom", "2");
   set("fullscreen", "false");
   set("grabmouse", "false");
+  set("center", "true");
   set("palette", "standard");
 
   set("sound", "true");
@@ -241,6 +242,7 @@ void Settings::usage()
     << "  -zoom         <size>         Makes window be 'size' times normal\n"
     << "  -fullscreen   <1|0>          Play the game in fullscreen mode\n"
     << "  -grabmouse    <1|0>          Keeps the mouse in the game window\n"
+    << "  -center       <1|0>          Centers game window (if possible)\n"
     << "  -palette      <original|     Use the specified color palette\n"
     << "                 standard|\n"
     << "                 z26>\n"
diff --git a/stella/src/gui/ByteGridWidget.cxx b/stella/src/gui/ByteGridWidget.cxx
index 1f2c1073d..7d6a419b5 100644
--- a/stella/src/gui/ByteGridWidget.cxx
+++ b/stella/src/gui/ByteGridWidget.cxx
@@ -13,7 +13,7 @@
 // See the file "license" for information on usage and redistribution of
 // this file, and for a DISCLAIMER OF ALL WARRANTIES.
 //
-// $Id: ByteGridWidget.cxx,v 1.2 2005-06-16 22:18:02 stephena Exp $
+// $Id: ByteGridWidget.cxx,v 1.3 2005-06-17 14:42:49 stephena Exp $
 //
 //   Based on code from ScummVM - Scumm Interpreter
 //   Copyright (C) 2002-2004 The ScummVM project
@@ -25,6 +25,7 @@
 #include "OSystem.hxx"
 #include "Widget.hxx"
 #include "Dialog.hxx"
+#include "Debugger.hxx"
 #include "FrameBuffer.hxx"
 #include "ByteGridWidget.hxx"
 
@@ -50,10 +51,7 @@ ByteGridWidget::ByteGridWidget(GuiObject* boss, int x, int y, int cols, int rows
   _type = kByteGridWidget;
   _editMode = false;
 
-  _currentPos = 0;
   _currentKeyDown = 0;
-	
-  _quickSelectTime = 0;
 
   // The item is selected, thus _bgcolor is used to draw the caret and
   // _textcolorhi to erase it
@@ -80,7 +78,7 @@ void ByteGridWidget::setList(const ByteAddrList& alist, const ByteValueList& vli
   _valueList = vlist;
 
   int size = _addrList.size();  // assume vlist is the same size
-//FIXME  assert(size != _rows * _cols);
+  assert(size == _rows * _cols);
 
   // An efficiency thing
   char temp[10];
@@ -92,13 +90,6 @@ void ByteGridWidget::setList(const ByteAddrList& alist, const ByteValueList& vli
     _valueStringList.push_back(temp);
   }
 
-  if (_currentPos >= size)
-    _currentPos = size - 1;
-  if (_currentPos < 0)
-    _currentPos = 0;
-  _selectedItem = 0;
-  _currentRow = 0;
-  _currentCol = 0;
   _editMode = false;
 }
 
@@ -296,9 +287,9 @@ void ByteGridWidget::handleCommand(CommandSender* sender, int cmd, int data)
   switch (cmd)
   {
     case kSetPositionCmd:
-      if (_currentPos != (int)data)
+      if (_selectedItem != (int)data)
       {
-        _currentPos = data;
+        _selectedItem = data;
         draw();
       }
       break;
@@ -396,7 +387,7 @@ void ByteGridWidget::endEditMode()
   _editMode = false;
 
   // Update the both the string representation and the real data
-  int value = atoi(_editString.c_str());
+  int value = Debugger::hex_to_dec(_editString.c_str());
   if(_editString.length() == 0 || value < 0 || value > 255)
   {
     abortEditMode();
@@ -404,10 +395,10 @@ void ByteGridWidget::endEditMode()
   }
 
   // Append a leading 0 when necessary
-  if(value < 10)
+  if(value < 16)  // In hex, this is the largest single-digit value
     _editString = "0" + _editString;
 
-  _valueStringList[_selectedItem] = _editString; // FIXME - make sure only length of 2
+  _valueStringList[_selectedItem] = _editString;
   _valueList[_selectedItem] = value;
 
   sendCommand(kBGItemDataChangedCmd, _selectedItem);
@@ -424,7 +415,9 @@ void ByteGridWidget::abortEditMode()
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 bool ByteGridWidget::tryInsertChar(char c, int pos)
 {
-  if (c >= '0' && c <= '9')
+  // Not sure how efficient this is, or should we even care?
+  c = tolower(c);
+  if (c >= '0' && c <= '9' || c >= 'a' && c <= 'f')
   {
     _editString.insert(pos, 1, c);
     return true;
diff --git a/stella/src/gui/ByteGridWidget.hxx b/stella/src/gui/ByteGridWidget.hxx
index ccedfe8f7..a33d2720e 100644
--- a/stella/src/gui/ByteGridWidget.hxx
+++ b/stella/src/gui/ByteGridWidget.hxx
@@ -13,7 +13,7 @@
 // See the file "license" for information on usage and redistribution of
 // this file, and for a DISCLAIMER OF ALL WARRANTIES.
 //
-// $Id: ByteGridWidget.hxx,v 1.2 2005-06-16 22:18:02 stephena Exp $
+// $Id: ByteGridWidget.hxx,v 1.3 2005-06-17 14:42:49 stephena Exp $
 //
 //   Based on code from ScummVM - Scumm Interpreter
 //   Copyright (C) 2002-2004 The ScummVM project
@@ -50,8 +50,8 @@ class ByteGridWidget : public EditableWidget, public CommandSender
 
     void setList(const ByteAddrList& alist, const ByteValueList& vlist);
 
-//    int getSelectedAddr() const   { return _addrList[_selectedItem]; }
-//    int getSelectedValue() const  { return _valueList[_selectedItem]; }
+    int getSelectedAddr() const   { return _addrList[_selectedItem]; }
+    int getSelectedValue() const  { return _valueList[_selectedItem]; }
 
     bool isEditable() const	         { return _editable; }
     void setEditable(bool editable)  { _editable = editable; }
@@ -93,14 +93,9 @@ class ByteGridWidget : public EditableWidget, public CommandSender
 
     bool    _editable;
     bool    _editMode;
-    int     _currentPos;
-    int     _entriesPerPage;
     int     _selectedItem;
     int     _currentKeyDown;
     string  _backupString;
-
-    string  _quickSelectStr;
-    int     _quickSelectTime;
 };
 
 #endif
diff --git a/stella/src/gui/DebuggerDialog.cxx b/stella/src/gui/DebuggerDialog.cxx
index e98c209dc..0b769a18a 100644
--- a/stella/src/gui/DebuggerDialog.cxx
+++ b/stella/src/gui/DebuggerDialog.cxx
@@ -13,20 +13,28 @@
 // See the file "license" for information on usage and redistribution of
 // this file, and for a DISCLAIMER OF ALL WARRANTIES.
 //
-// $Id: DebuggerDialog.cxx,v 1.12 2005-06-17 03:49:10 urchlay Exp $
+// $Id: DebuggerDialog.cxx,v 1.13 2005-06-17 14:42:49 stephena Exp $
 //
 //   Based on code from ScummVM - Scumm Interpreter
 //   Copyright (C) 2002-2004 The ScummVM project
 //============================================================================
 
+#include "Widget.hxx"
+#include "Dialog.hxx"
 #include "TabWidget.hxx"
 #include "ListWidget.hxx"
 #include "PromptWidget.hxx"
 #include "CheatWidget.hxx"
 #include "RamWidget.hxx"
+#include "Debugger.hxx"
 
 #include "DebuggerDialog.hxx"
 
+enum {
+  kDDStepCmd  = 'DDst',
+  kDDTraceCmd = 'DDtr'
+};
+
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 DebuggerDialog::DebuggerDialog(OSystem* osystem, DialogContainer* parent,
                                int x, int y, int w, int h)
@@ -34,13 +42,14 @@ DebuggerDialog::DebuggerDialog(OSystem* osystem, DialogContainer* parent,
     myTab(NULL)
 {
   const int vBorder = 4;
+  const int vWidth = _w - kButtonWidth - 20;
 
   // The tab widget
-  myTab = new TabWidget(this, 0, vBorder, _w, _h - vBorder - 1);
+  myTab = new TabWidget(this, 0, vBorder, vWidth, _h - vBorder - 1);
 
   // 1) The Prompt/console tab
   myTab->addTab("Prompt");
-  myPrompt = new PromptWidget(myTab, 2, 2, _w - vBorder, _h - 25);
+  myPrompt = new PromptWidget(myTab, 2, 2, vWidth - vBorder, _h - 25);
   myTab->setParentWidget(0, myPrompt, myPrompt);
 
   // 2) The CPU tab
@@ -49,7 +58,7 @@ DebuggerDialog::DebuggerDialog(OSystem* osystem, DialogContainer* parent,
 
   // 3) The RAM tab
   myTab->addTab("RAM");
-  RamWidget* ram = new RamWidget(myTab, 2, 2, _w - vBorder, _h - 25);
+  RamWidget* ram = new RamWidget(myTab, 2, 2, vWidth - vBorder, _h - 25);
   myTab->setParentWidget(2, ram, ram->activeWidget());
 
   // 4) The ROM tab
@@ -63,11 +72,17 @@ DebuggerDialog::DebuggerDialog(OSystem* osystem, DialogContainer* parent,
   // 6) The Cheat tab
   myTab->addTab("Cheat");
   CheatWidget* cheat = new CheatWidget(myTab, 2, 2,
-                                       _w - vBorder, _h - 25);
+                                       vWidth - vBorder, _h - 25);
   myTab->setParentWidget(5, cheat, cheat->activeWidget());
 
   // Set active tab to prompt
   myTab->setActiveTab(0);
+
+  // Add some buttons that are always shown, no matter which tab we're in
+  int yoff = vBorder + kTabHeight + 5;
+  addButton(vWidth + 10, yoff, "Step", kDDStepCmd, 0);
+  yoff += 22;
+  addButton(vWidth + 10, yoff, "Trace", kDDTraceCmd, 0);
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
@@ -78,6 +93,7 @@ DebuggerDialog::~DebuggerDialog()
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 void DebuggerDialog::loadConfig()
 {
+  myTab->loadConfig();
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
@@ -87,6 +103,27 @@ void DebuggerDialog::handleKeyDown(int ascii, int keycode, int modifiers)
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-PromptWidget *DebuggerDialog::prompt() {
+void DebuggerDialog::handleCommand(CommandSender* sender, int cmd, int data)
+{
+  switch(cmd)
+  {
+    case kDDStepCmd:
+      instance()->debugger().step();
+      myTab->loadConfig();  // make sure all the tabs are updated
+      break;
+
+    case kDDTraceCmd:
+      instance()->debugger().trace();
+      myTab->loadConfig();  // make sure all the tabs are updated
+      break;
+
+    default:
+      Dialog::handleCommand(sender, cmd, data);
+  }
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+PromptWidget *DebuggerDialog::prompt()
+{
   return myPrompt;
 }
diff --git a/stella/src/gui/DebuggerDialog.hxx b/stella/src/gui/DebuggerDialog.hxx
index 8f45b4c37..813446610 100644
--- a/stella/src/gui/DebuggerDialog.hxx
+++ b/stella/src/gui/DebuggerDialog.hxx
@@ -13,7 +13,7 @@
 // See the file "license" for information on usage and redistribution of
 // this file, and for a DISCLAIMER OF ALL WARRANTIES.
 //
-// $Id: DebuggerDialog.hxx,v 1.8 2005-06-17 03:49:10 urchlay Exp $
+// $Id: DebuggerDialog.hxx,v 1.9 2005-06-17 14:42:49 stephena Exp $
 //
 //   Based on code from ScummVM - Scumm Interpreter
 //   Copyright (C) 2002-2004 The ScummVM project
@@ -39,6 +39,7 @@ class DebuggerDialog : public Dialog
     PromptWidget *prompt();
     virtual void loadConfig();
     virtual void handleKeyDown(int ascii, int keycode, int modifiers);
+    virtual void handleCommand(CommandSender* sender, int cmd, int data);
 
   protected:
     TabWidget* myTab;
diff --git a/stella/src/gui/EditableWidget.cxx b/stella/src/gui/EditableWidget.cxx
index 7ba29f65c..1cdb08cc2 100644
--- a/stella/src/gui/EditableWidget.cxx
+++ b/stella/src/gui/EditableWidget.cxx
@@ -13,7 +13,7 @@
 // See the file "license" for information on usage and redistribution of
 // this file, and for a DISCLAIMER OF ALL WARRANTIES.
 //
-// $Id: EditableWidget.cxx,v 1.4 2005-06-16 18:40:17 stephena Exp $
+// $Id: EditableWidget.cxx,v 1.5 2005-06-17 14:42:49 stephena Exp $
 //
 //   Based on code from ScummVM - Scumm Interpreter
 //   Copyright (C) 2002-2004 The ScummVM project
@@ -127,7 +127,7 @@ bool EditableWidget::handleKeyDown(int ascii, int keycode, int modifiers)
     default:
       if (tryInsertChar((char)ascii, _caretPos))
       {
-	    _caretPos++;
+        _caretPos++;
         dirty = true;
       }
       else
diff --git a/stella/src/gui/RamWidget.cxx b/stella/src/gui/RamWidget.cxx
index ae7d71fa0..1704c52f5 100644
--- a/stella/src/gui/RamWidget.cxx
+++ b/stella/src/gui/RamWidget.cxx
@@ -13,7 +13,7 @@
 // See the file "license" for information on usage and redistribution of
 // this file, and for a DISCLAIMER OF ALL WARRANTIES.
 //
-// $Id: RamWidget.cxx,v 1.2 2005-06-16 22:18:02 stephena Exp $
+// $Id: RamWidget.cxx,v 1.3 2005-06-17 14:42:49 stephena Exp $
 //
 //   Based on code from ScummVM - Scumm Interpreter
 //   Copyright (C) 2002-2004 The ScummVM project
@@ -62,8 +62,6 @@ RamWidget::RamWidget(GuiObject* boss, int x, int y, int w, int h)
   myRamGrid->setTarget(this);
   myActiveWidget = myRamGrid;
 
-  fillGrid();
-
 #if 0
   const int border = 20;
   const int bwidth = 50;
@@ -130,35 +128,17 @@ void RamWidget::handleCommand(CommandSender* sender, int cmd, int data)
 {
   switch(cmd)
   {
-/*
-    case kBGItemDoubleClickedCmd:
-      cerr << "double-clicked on " << data << endl;
-      break;
-
-    case kBGItemActivatedCmd:
-      cerr << "item activated on " << data << endl;
-      break;
-
-    case kBGSelectionChangedCmd:
-      cerr << "selection changed on " << data << endl;
-      break;
-*/
     case kBGItemDataChangedCmd:
-      cerr << "data changed on " << data << endl;
-/*
-      int addr  = myResultsList->getSelectedAddr() - kRamStart;
-      int value = myResultsList->getSelectedValue();
+      int addr  = myRamGrid->getSelectedAddr() - kRamStart;
+      int value = myRamGrid->getSelectedValue();
       instance()->debugger().writeRAM(addr, value);
-*/
       break;
   }
 }
 
-
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 void RamWidget::loadConfig()
 {
-cerr << "RamWidget::loadConfig()\n";
   fillGrid();
 }
 
diff --git a/stella/src/gui/TabWidget.cxx b/stella/src/gui/TabWidget.cxx
index 219e6752f..0b5d72c80 100644
--- a/stella/src/gui/TabWidget.cxx
+++ b/stella/src/gui/TabWidget.cxx
@@ -13,7 +13,7 @@
 // See the file "license" for information on usage and redistribution of
 // this file, and for a DISCLAIMER OF ALL WARRANTIES.
 //
-// $Id: TabWidget.cxx,v 1.8 2005-06-16 22:18:02 stephena Exp $
+// $Id: TabWidget.cxx,v 1.9 2005-06-17 14:42:49 stephena Exp $
 //
 //   Based on code from ScummVM - Scumm Interpreter
 //   Copyright (C) 2002-2004 The ScummVM project
@@ -28,8 +28,6 @@
 #include "TabWidget.hxx"
 
 enum {
-  kTabHeight = 16,
-
   kTabLeftOffset = 4,
   kTabSpacing = 2,
   kTabPadding = 3
@@ -253,6 +251,21 @@ void TabWidget::handleCommand(CommandSender* sender, int cmd, int data)
   }
 }
 
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void TabWidget::loadConfig()
+{
+  // (Re)load the contents of all tabs
+  // It's up to each tab to decide if it wants to do anything on a reload
+  for (int id = 0; id < (int)_tabs.size(); ++id)
+  {
+    if(_tabs[id].parentWidget)
+      _tabs[id].parentWidget->loadConfig();
+  }
+
+  // Make sure changes are seen onscreen
+  instance()->frameBuffer().refresh();
+}
+
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 void TabWidget::box(int x, int y, int width, int height,
                     OverlayColor colorA, OverlayColor colorB, bool omitBottom)
@@ -300,11 +313,13 @@ void TabWidget::drawWidget(bool hilite)
     x += _tabWidth + kTabSpacing;
   }
 
-  // Draw more horizontal lines
+  // Draw a frame around the widget area (belows the tabs)
   fb.hLine(left1, _y + kTabHeight - 1, right1, kColor);
   fb.hLine(left2, _y + kTabHeight - 1, right2, kColor);
   fb.hLine(_x+1, _y + _h - 2, _x + _w - 2, kShadowColor);
   fb.hLine(_x+1, _y + _h - 1, _x + _w - 2, kColor);
+  fb.vLine(_x + _w - 2, _y + kTabHeight - 1, _y + _h - 2, kColor);
+  fb.vLine(_x + _w - 1, _y + kTabHeight - 1, _y + _h - 2, kShadowColor);
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
diff --git a/stella/src/gui/TabWidget.hxx b/stella/src/gui/TabWidget.hxx
index 0abe7830d..c7a1bcf07 100644
--- a/stella/src/gui/TabWidget.hxx
+++ b/stella/src/gui/TabWidget.hxx
@@ -13,7 +13,7 @@
 // See the file "license" for information on usage and redistribution of
 // this file, and for a DISCLAIMER OF ALL WARRANTIES.
 //
-// $Id: TabWidget.hxx,v 1.6 2005-06-16 22:18:02 stephena Exp $
+// $Id: TabWidget.hxx,v 1.7 2005-06-17 14:42:49 stephena Exp $
 //
 //   Based on code from ScummVM - Scumm Interpreter
 //   Copyright (C) 2002-2004 The ScummVM project
@@ -28,6 +28,10 @@
 #include "Array.hxx"
 #include "bspf.hxx"
 
+enum {
+  kTabHeight = 16
+};
+
 class TabWidget : public Widget, public CommandSender
 {
   struct Tab {
@@ -65,6 +69,8 @@ class TabWidget : public Widget, public CommandSender
     virtual bool handleKeyDown(int ascii, int keycode, int modifiers);
     virtual void handleCommand(CommandSender* sender, int cmd, int data);
 
+    virtual void loadConfig();
+
   protected:
     virtual void drawWidget(bool hilite);
     virtual Widget *findWidget(int x, int y);