GTK and Windows appear to handle timers very differently:

specifically, the elapsed time between calls varies much more with
GTK than it does under Windows. Therefore, I now take my own time
readings on every timer call, and this appears to have made the
animations run at closer to the same speed between platforms. Having
done that, I decided some of them were at the _wrong_ speed, and
fiddled with each game's timings as well.

[originally from svn r4189]

net.c

@@ -56,8 +56,8 @@ const int game_can_configure = TRUE;
 #define TILE_BORDER 1
 #define WINDOW_OFFSET 16
 
-#define ROTATE_TIME 0.1F
-#define FLASH_FRAME 0.05F
+#define ROTATE_TIME 0.13F
+#define FLASH_FRAME 0.07F
 
 enum {
     COL_BACKGROUND,