Xyga wrote:*wall of text*
tl;dr pls
P.S.: you should not use lcd in the mame.ini, you just have to adjust the CRT_range to what your monitor supports.
P.P.S.: GM runs with a graphic card as low as an AGP Radeon 7000 (that's what I used in my first build). Although I've discovered that newer ones have much nicer output, both in colors and sharpness over a CRT. If you need to use GLSL or filters, that's another can of worms, and then you need a decent graphic card.
And yeah, I agree that an updated guide for both CRT and LCD would be nice and should be included with the download, so when people start lamenting issue we can finally reply with the evergreen RTFM.