diff --git a/BizHawk.Common/Win32Hacks.cs b/BizHawk.Common/Win32Hacks.cs
index 7126f0e7b2..9770518d38 100644
--- a/BizHawk.Common/Win32Hacks.cs
+++ b/BizHawk.Common/Win32Hacks.cs
@@ -458,6 +458,14 @@ namespace BizHawk.Common
 		{
 			DeleteFileW(path + ":Zone.Identifier");
 		}
+
+		[DllImport("kernel32.dll")]
+		static extern bool IsDebuggerPresent();
+		
+		public static bool IsDebuggerReallyPresent()
+		{
+			return IsDebuggerPresent();
+		}
 	}
 
 }
\ No newline at end of file
diff --git a/BizHawk.Emulation.Cores/Consoles/Nintendo/SNES/LibsnesApi.cs b/BizHawk.Emulation.Cores/Consoles/Nintendo/SNES/LibsnesApi.cs
index 62ae3c73a7..545db1b271 100644
--- a/BizHawk.Emulation.Cores/Consoles/Nintendo/SNES/LibsnesApi.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Nintendo/SNES/LibsnesApi.cs
@@ -62,9 +62,11 @@ namespace BizHawk.Emulation.Cores.Nintendo.SNES
 				PlainHeapSizeKB = 2 * 1024, // TODO: wasn't there more in here?
 				SealedHeapSizeKB = 128 * 1024
 			});
-
-			_core = BizInvoker.GetInvoker<CoreImpl>(_exe, _exe);
-			_comm = (CommStruct*)_core.DllInit().ToPointer();
+			using (_exe.EnterExit())
+			{
+				_core = BizInvoker.GetInvoker<CoreImpl>(_exe, _exe);
+				_comm = (CommStruct*)_core.DllInit().ToPointer();
+			}
 		}
 
 		public void Dispose()
diff --git a/BizHawk.Emulation.Cores/Consoles/Nintendo/SNES/LibsnesCore.ISaveRam.cs b/BizHawk.Emulation.Cores/Consoles/Nintendo/SNES/LibsnesCore.ISaveRam.cs
index 0cf3e94476..67753f69d5 100644
--- a/BizHawk.Emulation.Cores/Consoles/Nintendo/SNES/LibsnesCore.ISaveRam.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Nintendo/SNES/LibsnesCore.ISaveRam.cs
@@ -2,6 +2,7 @@
 using System.Runtime.InteropServices;
 
 using BizHawk.Emulation.Common;
+using BizHawk.Common;
 
 namespace BizHawk.Emulation.Cores.Nintendo.SNES
 {
@@ -13,40 +14,46 @@ namespace BizHawk.Emulation.Cores.Nintendo.SNES
 
 		public byte[] CloneSaveRam()
 		{
-			byte* buf = Api.QUERY_get_memory_data(LibsnesApi.SNES_MEMORY.CARTRIDGE_RAM);
-			var size = Api.QUERY_get_memory_size(LibsnesApi.SNES_MEMORY.CARTRIDGE_RAM);
-			if (buf == null)
+			using (Api.EnterExit())
 			{
-				buf = Api.QUERY_get_memory_data(LibsnesApi.SNES_MEMORY.SGB_CARTRAM);
-				size = Api.QUERY_get_memory_size(LibsnesApi.SNES_MEMORY.SGB_CARTRAM);
-			}
+				byte* buf = Api.QUERY_get_memory_data(LibsnesApi.SNES_MEMORY.CARTRIDGE_RAM);
+				var size = Api.QUERY_get_memory_size(LibsnesApi.SNES_MEMORY.CARTRIDGE_RAM);
+				if (buf == null)
+				{
+					buf = Api.QUERY_get_memory_data(LibsnesApi.SNES_MEMORY.SGB_CARTRAM);
+					size = Api.QUERY_get_memory_size(LibsnesApi.SNES_MEMORY.SGB_CARTRAM);
+				}
 
-			var ret = new byte[size];
-			Marshal.Copy((IntPtr)buf, ret, 0, size);
-			return ret;
+				var ret = new byte[size];
+				Marshal.Copy((IntPtr)buf, ret, 0, size);
+				return ret;
+			}
 		}
 
 		public void StoreSaveRam(byte[] data)
 		{
-			byte* buf = Api.QUERY_get_memory_data(LibsnesApi.SNES_MEMORY.CARTRIDGE_RAM);
-			var size = Api.QUERY_get_memory_size(LibsnesApi.SNES_MEMORY.CARTRIDGE_RAM);
-			if (buf == null)
+			using (Api.EnterExit())
 			{
-				buf = Api.QUERY_get_memory_data(LibsnesApi.SNES_MEMORY.SGB_CARTRAM);
-				size = Api.QUERY_get_memory_size(LibsnesApi.SNES_MEMORY.SGB_CARTRAM);
-			}
+				byte* buf = Api.QUERY_get_memory_data(LibsnesApi.SNES_MEMORY.CARTRIDGE_RAM);
+				var size = Api.QUERY_get_memory_size(LibsnesApi.SNES_MEMORY.CARTRIDGE_RAM);
+				if (buf == null)
+				{
+					buf = Api.QUERY_get_memory_data(LibsnesApi.SNES_MEMORY.SGB_CARTRAM);
+					size = Api.QUERY_get_memory_size(LibsnesApi.SNES_MEMORY.SGB_CARTRAM);
+				}
 
-			if (size == 0)
-			{
-				return;
-			}
+				if (size == 0)
+				{
+					return;
+				}
 
-			if (size != data.Length)
-			{
-				throw new InvalidOperationException("Somehow, we got a mismatch between saveram size and what bsnes says the saveram size is");
-			}
+				if (size != data.Length)
+				{
+					throw new InvalidOperationException("Somehow, we got a mismatch between saveram size and what bsnes says the saveram size is");
+				}
 
-			Marshal.Copy(data, 0, (IntPtr)buf, size);
+				Marshal.Copy(data, 0, (IntPtr)buf, size);
+			}
 		}
 	}
 }
diff --git a/BizHawk.Emulation.Cores/Waterbox/PeRunner.cs b/BizHawk.Emulation.Cores/Waterbox/PeRunner.cs
index 8852d3588d..85a59ba762 100644
--- a/BizHawk.Emulation.Cores/Waterbox/PeRunner.cs
+++ b/BizHawk.Emulation.Cores/Waterbox/PeRunner.cs
@@ -734,8 +734,10 @@ namespace BizHawk.Emulation.Cores.Waterbox
 				_syscalls.Init();
 
 				Console.WriteLine("About to enter unmanaged code");
-				if (System.Diagnostics.Debugger.IsAttached)
+				if (Win32Hacks.IsDebuggerReallyPresent() && !System.Diagnostics.Debugger.IsAttached)
 				{
+					// this means that GDB or another unconventional debugger is attached.
+					// if that's the case, and it's observing this core, it probably wants a break
 					System.Diagnostics.Debugger.Break();
 				}
 
diff --git a/BizHawk.Emulation.Cores/Waterbox/Swappable.cs b/BizHawk.Emulation.Cores/Waterbox/Swappable.cs
index 25d3d8d0e9..2eff85f9a7 100644
--- a/BizHawk.Emulation.Cores/Waterbox/Swappable.cs
+++ b/BizHawk.Emulation.Cores/Waterbox/Swappable.cs
@@ -54,6 +54,12 @@ namespace BizHawk.Emulation.Cores.Waterbox
 		{
 			public object Sync;
 			private WeakReference LoadedRef = new WeakReference(null);
+#if DEBUG
+			/// <summary>
+			/// recursive lock count
+			/// </summary>
+			public int LockCount;
+#endif
 			public Swappable Loaded
 			{
 				get
@@ -78,6 +84,10 @@ namespace BizHawk.Emulation.Cores.Waterbox
 		public void Enter()
 		{
 			Monitor.Enter(_currentLockInfo.Sync);
+#if DEBUG
+			if (_currentLockInfo.LockCount++ != 0 && _currentLockInfo.Loaded != this)
+				throw new InvalidOperationException("Woops!");
+#endif
 			if (_currentLockInfo.Loaded != this)
 			{
 				if (_currentLockInfo.Loaded != null)
@@ -93,6 +103,16 @@ namespace BizHawk.Emulation.Cores.Waterbox
 		/// </summary>
 		public void Exit()
 		{
+#if DEBUG
+			// when debugging, if we're releasing the lock then deactivate
+			if (_currentLockInfo.LockCount-- == 1)
+			{
+				if (_currentLockInfo.Loaded != this)
+					throw new InvalidOperationException("Woops!");
+				DeactivateInternal();
+				_currentLockInfo.Loaded = null;
+			}
+#endif
 			Monitor.Exit(_currentLockInfo.Sync);
 		}