diff --git a/src/emucore/MD5.cxx b/src/emucore/MD5.cxx
index b0831b19e..4a0df33a0 100644
--- a/src/emucore/MD5.cxx
+++ b/src/emucore/MD5.cxx
@@ -168,8 +168,8 @@ void MD5::transform(const uInt8* const block)
   state[2] += c;
   state[3] += d;
 
-  // Zeroize sensitive information.
-  x.fill(0);
+  // Zeroize sensitive information (not required for Stella)
+  // x.fill(0);
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
@@ -237,9 +237,9 @@ void MD5::finalize()
     // Store state in digest
     encode(digest.data(), state.data(), 16);
 
-    // Zeroize sensitive information
-    buffer.fill(0);
-    count.fill(0);
+    // Zeroize sensitive information (not required for Stella)
+    // buffer.fill(0);
+    // count.fill(0);
 
     finalized = true;
   }
diff --git a/src/os/macos/SettingsRepositoryMACOS.hxx b/src/os/macos/SettingsRepositoryMACOS.hxx
index 667b4e343..fa57c25f5 100644
--- a/src/os/macos/SettingsRepositoryMACOS.hxx
+++ b/src/os/macos/SettingsRepositoryMACOS.hxx
@@ -23,9 +23,9 @@
 class SettingsRepositoryMACOS : public KeyValueRepository
 {
   public:
-    std::map<string, Variant> load() override;
+    KVRMap load() override;
 
-    bool save(const std::map<string, Variant>& values) override;
+    bool save(const KVRMap& values) override;
 };
 
 #endif // SETTINGS_REPOSITORY_MACOS_HXX
diff --git a/src/os/macos/SettingsRepositoryMACOS.mm b/src/os/macos/SettingsRepositoryMACOS.mm
index b13df2a98..69ab8ee2a 100644
--- a/src/os/macos/SettingsRepositoryMACOS.mm
+++ b/src/os/macos/SettingsRepositoryMACOS.mm
@@ -20,9 +20,9 @@
 #include "SettingsRepositoryMACOS.hxx"
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-std::map<string, Variant> SettingsRepositoryMACOS::load()
+KVRMap SettingsRepositoryMACOS::load()
 {
-  std::map<string, Variant> values;
+  KVRMap values;
 
   @autoreleasepool {
     NSString* bundleId = [[NSBundle mainBundle] bundleIdentifier];
@@ -40,7 +40,7 @@ std::map<string, Variant> SettingsRepositoryMACOS::load()
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-bool SettingsRepositoryMACOS::save(const std::map<string, Variant>& values)
+bool SettingsRepositoryMACOS::save(const KVRMap& values)
 {
   @autoreleasepool {
     NSUserDefaults* defaults = [NSUserDefaults standardUserDefaults];