I'm not sure if software list games are supported by romcenter (I can't find it) but I would like to request this feature.
A nice way would be at the left treeview to add a subnode “Software List” with subnodes for all software lists currently extracted from -listsoftware (from mame exe) and added to the database. The normal Mame games (all non-software list games) could maybe be put in a subnode “Main List” or just “Mame” (or any better name for this).
If a user clicks a software list name, the roms of'that software list are displayed in the left rom list.
The scan and fix features should work exactly the same as they are now, but applied to software list roms.