You can download an up-to-date version of the AGS engine and put the executable into the game's folder to run it. This provides better performance and compatibility.

Could mike or someone elaborate on this please? I am a bit confused about AGS engine vs AGS editor. The way I'm reading this, is that I should download an editor release, and then place its executable inside the Maniac Mansion Deluxe game folder - which sounds wild to me :)

I did it anyway, and both of the two executables (acwin; AGSEditor) are producing errors.

Could you elaborate on how this works exactly, and how to set it up? Thank you

On another note: Running MMD through ScummVM these days removes a lot of the UI related performance bugs and issues. Are these the issues that this fix is addressing?

It should be the acwin.exe, but I just tried to run the game with the current AGS version and I also got an error on my system. Looks like this method might no longer be compatible with this old game.

ScummVM is probably the best bet nowadays. It's also almost the same thing anyway, since they basically bundle the modern AGS engine into ScummVM (but then also add per-game fixes to make sure everything works).