OK. I'll have to poke around on the Attract Mode forums and see how it deals with Software Lists to make sure before I spend a lot of time and bandwidth on this.
I had one more question. I noticed that a certain site that shall remain nameless has these two sets...
MAME 0.198 ROMs (bios-devices) MAME 0.198 Software List ROMs (machines-bios-devices)
Are they required now are they already incorporated into these other sets?...
MAME 0.198 ROMs (merged) MAME 0.198 Software List ROMs (merged)