> Hrm, I think for some reason ClrMame stopped doing this, as I had "Hide All" on

If Hide all is on, it automatically splits up the parent/clone relationship.


> Why it broke so many of my sets is that it probably tried to merge them back
> into the same file, and didn't backup the file it

Nope. All files are backuped before they get replaced. So most likely you only have to run a rebuild on the backup folder to readd them.


Roman Scherzer