Hi guys, sorry I didn't answer before, I'm very busy these days.
Some hints:
- Don't launch games from the menu inside GroovyMAME, if you do that it will default to 640x480 and resolution settings won't be applied (this will be fixed in next release.
- What you have to do is to launch games using a full command line, like this: groovymame.exe romname
- That's what properly setup frontends do for you BTW, that's why launching games from HS is working fine.
- You actually need mame.ini there for things to be perfect, specially if you own some fancy monitor, otherwise only default settings for a CGA monitor will be applied.
- GroovyMAME can't dynamically recalculate modelines for the AVGA, so it will use native AVGA modes that best fit your monitor, provided, you let it know which monitor you have.
- Some games may still have issues, like 1941 you mentioned, check this thread about getting logs, those are highly helpful for us to fix existing issues:
http://forum.arcadecontrols.com/index.php?topic=113382.0