I didn't see this posted any where, and it's probably a very simple and silly thing I'm overlooking, but!
Apparently the ISO is some brand of magical 'compiled into one 'DVD'' thing, and PCSX2 .9.7 doesn't seem to want to load it. I'm surmising I need a third item (Multiloader or summat?) to get it to load appropriately, but I'll be danged if I know what it is, where to get it, or how it functions. :O
Don't suppose anyone that is smurter than I can lend a hand?