I know from personal experience that the Matrox G4X0 series have crappy support for OpenGL on Linux systems (but this could've changed in the past year).
Perhaps you could try upgrading your GLX items to the latest version and test OpenGL with it.
Concering the bug when you put a commandline switch before the rom name, it's not a bug
In the docs as well as in the switches output it clearly states that the ROM name should be put as 1st option, switches as last items.
That we don't check about an non-existent switch, that is a bug. Fix should be available on CVS in the couple of days (as soon as I have time for it).
Regards,
Niels Wagenaar
http://sdlemu.ngemu.com