Thanks to the person that did find the hang bug in Operation Wolf - that's the first game I've found that's actually locked up.
Area 51 - is game requires hard drive files and a CHD file - were things set up properly for this game? Please double check.
Ok, because I promised, here are a list of games that do not run in MAMEoX:
Lockups
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Operation Wolf (locks up) (fixed in CVS build now)
Lethal Enforcers (locks up)
Out of Memory
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Vasara
Vasara2
Quiz de Idol Hot Debut
Metal Slug 3
Metal Slug X
Mars Matrix Hyper Solid Shooting
Lode Runner - The Dig Fight
Armed Police Batrider
Gals Panic 4
Gals Panic S
Gals Panic S2
Violent Storm
Primal Rage
Guwange
Gunbird 2
Ground Effects
Real Bout Fatal Fury Special (loads if sound is disabled)
Sengoku 3
Sengeki Striker
Run And Gun
Dragonball Z
Dragonball Z 2
Street Fighter Alpha 3
Vampire Savior
X-Men Children of the Atom
Street Fighter (yes, 1, not 2)
King of Fighters 97/98/99/2000/2001
Last Blade 1/2
ESP Ra.de
Sexy Parodius
Marvel Super Heroes
Playability issues
-----------------------
Stun Runner (sound issues, choppy)
NBA Jam (sound issues, choppy)
NBA Jam TE (sound issues, choppy)
Keep em coming guys. The hangs are the big ones, and I haven't been able to find any so far except for the ones you've posted.
Once I've got a more complete list I'll work on an xml file that you can put in your GENERAL directory that will indicate status of roms (so you'll know to keep away, and we'll know where to focus our effort).