First off, both Visual Pinball and VPinMAME are still betas. Both should be getting updates soon.
The ROMs issues will be fixed hopefully next release of VPinMAME, and may actually throw out this entire .dat issue, and just stick to the roms that are the actual pinball arcade roms.
What you mean by problem games? Some of these games, the roms just don't work, or the roms are not complete. (Been working on that the last few days, made some major progress)

Paul
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