Looking at the dbp (I was able to unpack it using 7z fwiw) it looks like inside the appdata folder for this program you need to create folders lib/libretro and inside that put .so files, so if they come as zips I'd suggest unpacking them and see if you get an .so file from them.I wonder, when I want to add the nestopia core, how will this work:
Just download, put the zip in a folder, and then just running the NES Roms ?
And how well dos the vice C64 and the scummvm runs??
Maybe I have to play around a lot whit retroarch this afternoon..