diff --git a/src/xenia/gpu/d3d11/d3d11_shader_translator.cc b/src/xenia/gpu/d3d11/d3d11_shader_translator.cc
index ef8b75650..549f0c72d 100644
--- a/src/xenia/gpu/d3d11/d3d11_shader_translator.cc
+++ b/src/xenia/gpu/d3d11/d3d11_shader_translator.cc
@@ -163,8 +163,10 @@ int D3D11ShaderTranslator::TranslateVertexShader(
     "  VS_OUTPUT o;\n");
 
   // Always write position, as some shaders seem to only write certain values.
-  append(
-    "  o.oPos = float4(0.0, 0.0, 0.0, 0.0);\n");
+  if (alloc_counts.positions) {
+    append(
+      "  o.oPos = float4(0.0, 0.0, 0.0, 0.0);\n");
+  }
   if (alloc_counts.point_size) {
     append(
       "  o.oPointSize = float4(1.0, 0.0, 0.0, 0.0);\n");
@@ -198,8 +200,11 @@ int D3D11ShaderTranslator::TranslateVertexShader(
   }
 
   // main footer.
+  if (alloc_counts.positions) {
+    append(
+      "  o.oPos = applyViewport(o.oPos);\n");
+  }
   append(
-    "  o.oPos = applyViewport(o.oPos);\n"
     "  return o;\n"
     "};\n");
 
diff --git a/src/xenia/kernel/kernel_state.cc b/src/xenia/kernel/kernel_state.cc
index 5cd6110b7..bc10751d7 100644
--- a/src/xenia/kernel/kernel_state.cc
+++ b/src/xenia/kernel/kernel_state.cc
@@ -16,6 +16,7 @@
 #include <xenia/kernel/xboxkrnl_private.h>
 #include <xenia/kernel/xobject.h>
 #include <xenia/kernel/objects/xmodule.h>
+#include <xenia/kernel/objects/xnotify_listener.h>
 #include <xenia/kernel/objects/xthread.h>
 #include <xenia/kernel/objects/xuser_module.h>
 
@@ -135,3 +136,30 @@ XThread* KernelState::GetThreadByID(uint32_t thread_id) {
   xe_mutex_unlock(object_mutex_);
   return thread;
 }
+
+void KernelState::RegisterNotifyListener(XNotifyListener* listener) {
+  xe_mutex_lock(object_mutex_);
+  notify_listeners_.push_back(listener);
+  xe_mutex_unlock(object_mutex_);
+}
+
+void KernelState::UnregisterNotifyListener(XNotifyListener* listener) {
+  xe_mutex_lock(object_mutex_);
+  for (auto it = notify_listeners_.begin(); it != notify_listeners_.end();
+       ++it) {
+    if (*it == listener) {
+      notify_listeners_.erase(it);
+      break;
+    }
+  }
+  xe_mutex_unlock(object_mutex_);
+}
+
+void KernelState::BroadcastNotification(XNotificationID id, uint32_t data) {
+  xe_mutex_lock(object_mutex_);
+  for (auto it = notify_listeners_.begin(); it != notify_listeners_.end();
+       ++it) {
+    (*it)->EnqueueNotification(id, data);
+  }
+  xe_mutex_unlock(object_mutex_);
+}
diff --git a/src/xenia/kernel/kernel_state.h b/src/xenia/kernel/kernel_state.h
index 944169918..f2fb3f47e 100644
--- a/src/xenia/kernel/kernel_state.h
+++ b/src/xenia/kernel/kernel_state.h
@@ -23,6 +23,7 @@ XEDECLARECLASS1(xe, Emulator);
 XEDECLARECLASS2(xe, cpu, Processor);
 XEDECLARECLASS2(xe, kernel, Dispatcher);
 XEDECLARECLASS2(xe, kernel, XModule);
+XEDECLARECLASS2(xe, kernel, XNotifyListener);
 XEDECLARECLASS2(xe, kernel, XThread);
 XEDECLARECLASS2(xe, kernel, XUserModule);
 XEDECLARECLASS3(xe, kernel, fs, FileSystem);
@@ -56,6 +57,10 @@ public:
   void UnregisterThread(XThread* thread);
   XThread* GetThreadByID(uint32_t thread_id);
 
+  void RegisterNotifyListener(XNotifyListener* listener);
+  void UnregisterNotifyListener(XNotifyListener* listener);
+  void BroadcastNotification(XNotificationID id, uint32_t data);
+
 private:
   Emulator*       emulator_;
   Memory*         memory_;
@@ -67,6 +72,7 @@ private:
   ObjectTable*    object_table_;
   xe_mutex_t*     object_mutex_;
   std::unordered_map<uint32_t, XThread*> threads_by_id_;
+  std::vector<XNotifyListener*> notify_listeners_;
 
   XUserModule*    executable_module_;
 
diff --git a/src/xenia/kernel/objects/xnotify_listener.cc b/src/xenia/kernel/objects/xnotify_listener.cc
index b9d45dafb..7e9ffb704 100644
--- a/src/xenia/kernel/objects/xnotify_listener.cc
+++ b/src/xenia/kernel/objects/xnotify_listener.cc
@@ -20,6 +20,7 @@ XNotifyListener::XNotifyListener(KernelState* kernel_state) :
 }
 
 XNotifyListener::~XNotifyListener() {
+  kernel_state_->UnregisterNotifyListener(this);
   xe_mutex_free(lock_);
   if (wait_handle_) {
     CloseHandle(wait_handle_);
@@ -32,9 +33,16 @@ void XNotifyListener::Initialize(uint64_t mask) {
   lock_ = xe_mutex_alloc();
   wait_handle_ = CreateEvent(NULL, TRUE, FALSE, NULL);
   mask_ = mask;
+
+  kernel_state_->RegisterNotifyListener(this);
 }
 
 void XNotifyListener::EnqueueNotification(XNotificationID id, uint32_t data) {
+  // Ignore if the notification doesn't match our mask.
+  if ((mask_ & uint64_t(1 << ((id >> 25) + 1))) == 0) {
+    return;
+  }
+
   xe_mutex_lock(lock_);
   auto existing = notifications_.find(id);
   if (existing != notifications_.end()) {
diff --git a/src/xenia/kernel/objects/xnotify_listener.h b/src/xenia/kernel/objects/xnotify_listener.h
index a7aa16eee..436c4434a 100644
--- a/src/xenia/kernel/objects/xnotify_listener.h
+++ b/src/xenia/kernel/objects/xnotify_listener.h
@@ -21,9 +21,6 @@
 namespace xe {
 namespace kernel {
 
-// Values seem to be all over the place - GUIDs?
-typedef uint32_t XNotificationID;
-
 
 class XNotifyListener : public XObject {
 public:
diff --git a/src/xenia/kernel/util/xex2.cc b/src/xenia/kernel/util/xex2.cc
index af71eb182..1aca590e3 100644
--- a/src/xenia/kernel/util/xex2.cc
+++ b/src/xenia/kernel/util/xex2.cc
@@ -11,6 +11,7 @@
 
 #include <vector>
 
+#include <gflags/gflags.h>
 #include <third_party/crypto/rijndael-alg-fst.h>
 #include <third_party/crypto/rijndael-alg-fst.c>
 #include <third_party/mspack/lzx.h>
@@ -20,6 +21,8 @@
 
 using namespace alloy;
 
+DEFINE_bool(xex_dev_key, false, "Use the devkit key.");
+
 
 typedef struct xe_xex2 {
   xe_ref_t ref;
@@ -434,7 +437,7 @@ int xe_xex2_decrypt_key(xe_xex2_header_t *header) {
   // Guess key based on file info.
   // TODO: better way to finding out which key to use?
   const uint8_t *xexkey;
-  if (header->execution_info.title_id) {
+  if (header->execution_info.title_id && !FLAGS_xex_dev_key) {
     xexkey = xe_xex2_retail_key;
   } else {
     xexkey = xe_xex2_devkit_key;
diff --git a/src/xenia/kernel/xam_user.cc b/src/xenia/kernel/xam_user.cc
index ebe48c2cb..005475812 100644
--- a/src/xenia/kernel/xam_user.cc
+++ b/src/xenia/kernel/xam_user.cc
@@ -174,6 +174,23 @@ SHIM_CALL XamUserReadProfileSettings_shim(
 }
 
 
+SHIM_CALL XamShowSigninUI_shim(
+    PPCContext* ppc_state, KernelState* state) {
+  uint32_t unk_0 = SHIM_GET_ARG_32(0);
+  uint32_t unk_mask = SHIM_GET_ARG_32(1);
+
+  XELOGD(
+      "XamShowSigninUI(%d, %.8X)",
+      unk_0, unk_mask);
+
+  // Mask values vary. Probably matching user types? Local/remote?
+  // Games seem to sit and loop until we trigger this notification.
+  state->BroadcastNotification(0x00000009, 0);
+
+  SHIM_SET_RETURN_32(X_ERROR_SUCCESS);
+}
+
+
 }  // namespace kernel
 }  // namespace xe
 
@@ -185,4 +202,5 @@ void xe::kernel::xam::RegisterUserExports(
   SHIM_SET_MAPPING("xam.xex", XamUserGetSigninInfo, state);
   SHIM_SET_MAPPING("xam.xex", XamUserGetName, state);
   SHIM_SET_MAPPING("xam.xex", XamUserReadProfileSettings, state);
+  SHIM_SET_MAPPING("xam.xex", XamShowSigninUI, state);
 }
diff --git a/src/xenia/kernel/xboxkrnl_threading.cc b/src/xenia/kernel/xboxkrnl_threading.cc
index c7f31aee0..0e119491b 100644
--- a/src/xenia/kernel/xboxkrnl_threading.cc
+++ b/src/xenia/kernel/xboxkrnl_threading.cc
@@ -1129,7 +1129,7 @@ SHIM_CALL NtWaitForSingleObjectEx_shim(
     uint64_t timeout = timeout_ptr ? SHIM_MEM_64(timeout_ptr) : 0;
     result = object->Wait(
         3, wait_mode, alertable,
-    timeout_ptr ? &timeout : NULL);
+        timeout_ptr ? &timeout : NULL);
     object->Release();
   }
 
diff --git a/src/xenia/xbox.h b/src/xenia/xbox.h
index aab667584..9f3a6b071 100644
--- a/src/xenia/xbox.h
+++ b/src/xenia/xbox.h
@@ -254,6 +254,10 @@ public:
 };
 
 
+// Values seem to be all over the place - GUIDs?
+typedef uint32_t XNotificationID;
+
+
 typedef enum _X_INPUT_FLAG {
   X_INPUT_FLAG_GAMEPAD      = 0x00000001,
 } X_INPUT_FLAG;