diff --git a/inc/fps_limiter.h b/inc/fps_limiter.h
index 5e9d098..911225b 100644
--- a/inc/fps_limiter.h
+++ b/inc/fps_limiter.h
@@ -22,6 +22,12 @@ typedef struct _D3DKMT_CLOSEADAPTER {
     UINT hAdapter;
 } D3DKMT_CLOSEADAPTER;
 
+typedef HRESULT(WINAPI* DWMFLUSHPROC)(VOID);
+typedef HRESULT(WINAPI* DWMISCOMPOSITIONENABLEDPROC)(BOOL*);
+typedef NTSTATUS(WINAPI* D3DKMTWAITFORVERTICALBLANKEVENTPROC)(const D3DKMT_WAITFORVERTICALBLANKEVENT* Arg1);
+typedef NTSTATUS(WINAPI* D3DKMTOPENADAPTERFROMHDCPROC)(D3DKMT_OPENADAPTERFROMHDC* Arg1);
+typedef NTSTATUS(WINAPI* D3DKMTCLOSEADAPTERPROC)(D3DKMT_CLOSEADAPTER* Arg1);
+
 typedef struct fps_limiter
 {
     DWORD tick_start;
@@ -35,11 +41,11 @@ typedef struct fps_limiter
     D3DKMT_CLOSEADAPTER close_adapter;
     HMODULE gdi32_dll;
     HMODULE dwmapi_dll;
-    HRESULT(WINAPI* DwmFlush)(VOID);
-    HRESULT(WINAPI* DwmIsCompositionEnabled)(BOOL*);
-    NTSTATUS(WINAPI* D3DKMTWaitForVerticalBlankEvent)(const D3DKMT_WAITFORVERTICALBLANKEVENT* Arg1);
-    NTSTATUS(WINAPI* D3DKMTOpenAdapterFromHdc)(D3DKMT_OPENADAPTERFROMHDC* Arg1);
-    NTSTATUS(WINAPI* D3DKMTCloseAdapter)(D3DKMT_CLOSEADAPTER* Arg1);
+    DWMFLUSHPROC DwmFlush;
+    DWMISCOMPOSITIONENABLEDPROC DwmIsCompositionEnabled;
+    D3DKMTWAITFORVERTICALBLANKEVENTPROC D3DKMTWaitForVerticalBlankEvent;
+    D3DKMTOPENADAPTERFROMHDCPROC D3DKMTOpenAdapterFromHdc;
+    D3DKMTCLOSEADAPTERPROC D3DKMTCloseAdapter;
     BOOL got_adapter;
 } fps_limiter;
 
diff --git a/src/fps_limiter.c b/src/fps_limiter.c
index 0cf4a94..61fd4c0 100644
--- a/src/fps_limiter.c
+++ b/src/fps_limiter.c
@@ -39,22 +39,19 @@ void fpsl_init()
         g_fpsl.dwmapi_dll = LoadLibraryA("dwmapi.dll");
 
     g_fpsl.DwmFlush =
-        (HRESULT(WINAPI*)(VOID))GetProcAddress(g_fpsl.dwmapi_dll, "DwmFlush");
+        (DWMFLUSHPROC)GetProcAddress(g_fpsl.dwmapi_dll, "DwmFlush");
 
     g_fpsl.DwmIsCompositionEnabled =
-        (HRESULT(WINAPI*)(BOOL*))GetProcAddress(g_fpsl.dwmapi_dll, "DwmIsCompositionEnabled");
+        (DWMISCOMPOSITIONENABLEDPROC)GetProcAddress(g_fpsl.dwmapi_dll, "DwmIsCompositionEnabled");
 
     g_fpsl.D3DKMTWaitForVerticalBlankEvent =
-        (NTSTATUS(WINAPI*)(const D3DKMT_WAITFORVERTICALBLANKEVENT * Arg1))
-        GetProcAddress(g_fpsl.gdi32_dll, "D3DKMTWaitForVerticalBlankEvent");
+        (D3DKMTWAITFORVERTICALBLANKEVENTPROC)GetProcAddress(g_fpsl.gdi32_dll, "D3DKMTWaitForVerticalBlankEvent");
 
     g_fpsl.D3DKMTOpenAdapterFromHdc =
-        (NTSTATUS(WINAPI*)(D3DKMT_OPENADAPTERFROMHDC * Arg1))
-        GetProcAddress(g_fpsl.gdi32_dll, "D3DKMTOpenAdapterFromHdc");
+        (D3DKMTOPENADAPTERFROMHDCPROC)GetProcAddress(g_fpsl.gdi32_dll, "D3DKMTOpenAdapterFromHdc");
 
     g_fpsl.D3DKMTCloseAdapter =
-        (NTSTATUS(WINAPI*)(D3DKMT_CLOSEADAPTER * Arg1))
-        GetProcAddress(g_fpsl.gdi32_dll, "D3DKMTCloseAdapter");
+        (D3DKMTCLOSEADAPTERPROC)GetProcAddress(g_fpsl.gdi32_dll, "D3DKMTCloseAdapter");
 }
 
 BOOL fpsl_wait_for_vblank()
diff --git a/src/wndproc.c b/src/wndproc.c
index c683160..f3503f4 100644
--- a/src/wndproc.c
+++ b/src/wndproc.c
@@ -380,15 +380,26 @@ LRESULT CALLBACK fake_WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam
         case WM_NCMOUSELEAVE:
         {
             if (!g_ddraw->wine) /* hack: disable aero snap */
-                real_SetWindowLongA(g_ddraw->hwnd, GWL_STYLE, GetWindowLong(g_ddraw->hwnd, GWL_STYLE) | WS_MAXIMIZEBOX);
+            {
+                LONG style = GetWindowLong(g_ddraw->hwnd, GWL_STYLE);
 
+                if (!(style & WS_MAXIMIZEBOX))
+                {
+                    real_SetWindowLongA(g_ddraw->hwnd, GWL_STYLE, style | WS_MAXIMIZEBOX);
+                }
+            }
             break;
         }
         case WM_SYSCOMMAND:
 
             if ((wParam & ~0x0F) == SC_MOVE && !g_ddraw->wine) /* hack: disable aero snap */
             {
-                real_SetWindowLongA(g_ddraw->hwnd, GWL_STYLE, GetWindowLong(g_ddraw->hwnd, GWL_STYLE) & ~WS_MAXIMIZEBOX);
+                LONG style = GetWindowLong(g_ddraw->hwnd, GWL_STYLE);
+
+                if ((style & WS_MAXIMIZEBOX))
+                {
+                    real_SetWindowLongA(g_ddraw->hwnd, GWL_STYLE, style & ~WS_MAXIMIZEBOX);
+                }
             }
 
             if (wParam == SC_MAXIMIZE)