is it important if it's a LS type or does it have to be HC/HCT?
LS and HCT should both work fine, but with HCT you also need to connect all the unused inputs (pins 5,6,8,9,11,12 in the schematic above) which complicates a bit the wiring in this case.
Depending on the specific application, HC might be unreliable when drived by TTL logic because uses different swithcing voltage levels, so I'd avoid that.
Do you know why all the PAL versions of the 32k games are 48k?
I don't know. I'm more a 2600 enthusiast and not very familiar with the 7800...
First I've tried to write leave the 16k blank, but that didn't work, so I've put some 16k junk data in and that worked out nicely.
Don't know what happened. The lower 16k of the eprom are never accessed by the console, so it doesn't matter what's in there. If the eprom programmer software allows to start burning from a specific address, you should be able to just burn the 48k binary, else if it only accepts binary of the same size of the eprom you have to pad the first 16k with some data.
Thanks again for taking the time to help me out, much appreciated.
No problem, I'm glad you got it to work!
Edited by alex_79, Fri Oct 14, 2016 2:45 PM.