diff --git a/src/emucore/CartE7.cxx b/src/emucore/CartE7.cxx
index 7b8337e1f..3752e28b8 100644
--- a/src/emucore/CartE7.cxx
+++ b/src/emucore/CartE7.cxx
@@ -47,7 +47,7 @@ uInt16 CartridgeE7::bankCount() const
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-uInt32 CartridgeE7::romSize()
+uInt32 CartridgeE7::romSize() const
 {
   return bankCount() * BANK_SIZE;
 }
diff --git a/src/emucore/CartE7.hxx b/src/emucore/CartE7.hxx
index 1ca5b0314..e2fa40965 100644
--- a/src/emucore/CartE7.hxx
+++ b/src/emucore/CartE7.hxx
@@ -74,7 +74,7 @@ class CartridgeE7 : public CartridgeMNetwork
     /**
       Query the size of the BS type.
     */
-    uInt32 romSize() override;
+    uInt32 romSize() const override;
 
     /**
       Check hotspots and switch bank if triggered.
diff --git a/src/emucore/CartE78K.cxx b/src/emucore/CartE78K.cxx
index d31bf8b35..7d9604a76 100644
--- a/src/emucore/CartE78K.cxx
+++ b/src/emucore/CartE78K.cxx
@@ -47,7 +47,7 @@ uInt16 CartridgeE78K::bankCount() const
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-uInt32 CartridgeE78K::romSize()
+uInt32 CartridgeE78K::romSize() const
 {
   return bankCount() * BANK_SIZE;
 }
diff --git a/src/emucore/CartE78K.hxx b/src/emucore/CartE78K.hxx
index 6d3fcfbd7..dd08cb61d 100644
--- a/src/emucore/CartE78K.hxx
+++ b/src/emucore/CartE78K.hxx
@@ -72,7 +72,8 @@ class CartridgeE78K : public CartridgeMNetwork
     /**
       Query the size of the BS type.
     */
-    uInt32 romSize() override;
+    uInt32 romSize() const override;
+
     /**
       Check hotspots and switch bank if triggered.
     */
diff --git a/src/emucore/CartMNetwork.cxx b/src/emucore/CartMNetwork.cxx
index 2ad748805..7a7568d9d 100644
--- a/src/emucore/CartMNetwork.cxx
+++ b/src/emucore/CartMNetwork.cxx
@@ -86,6 +86,8 @@ void CartridgeMNetwork::install(System& system)
     access.codeAccessBase = &myCodeAccessBase[0x1fc0];
     mySystem->setPageAccess(addr, access);
   }
+  /*setAccess(0x1FE0 & ~System::PAGE_MASK, System::PAGE_SIZE,
+            0, nullptr, 0x1fc0, System::PA_NONE, 0x1fc0);*/
 
   // Setup the second segment to always point to the last ROM slice
   setAccess(0x1A00, 0x1FE0U & ~System::PAGE_MASK - 0x1A00,
diff --git a/src/emucore/CartMNetwork.hxx b/src/emucore/CartMNetwork.hxx
index 63c29370e..af79a1fa0 100644
--- a/src/emucore/CartMNetwork.hxx
+++ b/src/emucore/CartMNetwork.hxx
@@ -176,7 +176,7 @@ class CartridgeMNetwork : public Cartridge
     /**
       Query the size of the BS type.
     */
-    virtual uInt32 romSize() = 0;
+    virtual uInt32 romSize() const = 0;
 
     /**
       Check hotspots and switch bank if triggered.