WinTab32.dll is a library/DLL/API used to communicate with your stylus/tablet (Wacom, etc.). Sometimes, when we load this DLL the program just hangs. We don't know why this happen, but there are few users experimenting this (maybe a buggy WinTab32.dll, or maybe a buggy Aseprite).

Sometimes the problem is solved reinstalling the driver, sometimes the problem persists. In these cases you can execute Aseprite with --disable-wintab parameter (available since Aseprite v1.2):

"C:\Program Files\Aseprite\Aseprite.exe" --disable-wintab

This will bypass the WinTab32.dll loading process. Your stylus might not work correctly, but at least Aseprite can be executed and used with your mouse/trackpad.