> I wouldn't trust mame32's audit system, neither the >number of available sets.

I'm not sure I've made myself entirely clear: The display MAME32 has for ROM numbers is actually bottom right of the emulator when looking at Available, not the internal audit display. Or in other words, there were 796 ROMS Available to be played under MAME32, and after a scan and fix there were only 754. 42 Roms have thus been merged or broken in some way, and MAME no longer sees them.

>And don't forget that MAME32 needs
>manual gamelist refreshs after changing anything.

And that is after swapping to another grouping column, hitting F5, and returning to Available again. The loss of 42 was revealed after a manual MAME32 refresh

> Simply turn on all check/fix options in cmpro, turn on >nodump handling->show missing and run clrmamepro (add >missing files of course) until it shows no more
> errors.

I don't understand this point, I am sorry. Do you mean check "Create Missing" under "NoDump Handling"? Because this is the only difference I can see between what I did and what you suggest. But as I say I've lost ROMS, and not repaired ROMs, despite CLR now only seeing 1 error, in a BIOS. Nor am I understanding where I go from the situation I outlined below... thank you for your patience so far, but I must ask the same questions again I am afraid...