While this does close small memory leaks, this is mostly for threading reasons. We're not supposed to call rb_raise with the gvl released, and calling rb_raise prevents GFX_UNLOCK from being called, which would cause problems for any games that want to call graphical operations in multiple threads should the user reset.
We're also now calling Graphics.__reset__ and Audio.__reset__ via eval instead of directly calling the functions, in case a game wants to hook them.
rb_raise calls longjmp, which bypasses C++ destructors, and also keeps the error for catch blocks from being unallocated if passed by reference, which we do for exceptions.
Some of the calls I left can still jump out of try blocks, which you're not supposed to do, but there shouldn't be any objects with destructors initialized at those points so it's probably fine.
+ Time is now measured in fractions of a second, not microseconds
+ Viewports in RGSS1 will now only retain weak references to their children
+ Invalid Sprite bitmaps found during Graphics.update will be treated as null
+ Bitmap#mega? and Bitmap#animated? are properly rescued