I haven't looked at that skin ages, but here are some general tips:
Open the skin editor and click on the category
Now if you select the "Event" tab, it will indicate any events associated with the category
OR
Click on the "Category" tab the its "Event" tab and see if events are tied at that point.
Once you can figure out what is triggering the event to start play and load rom, then you can go into setup (F2), click on "Events" and drill down to see the command and how it is configured (what arguments and parameters to use).
The other thing to look for is under "Files" (gees you'd think I'd remember the tab title as I was just in there last night
) tab. There you can see executables with there associated file types and parameters, which is also used at times to launch the player/game required.
Hope this was of some help.