A7800 Emulator Problem - Not Found in FAQ/Readme

I downloaded a a couple of 7800 games... I followed all the directions but the .A78 game files won't load. I wish I could upload a screenshot but I keep getting a message saying something about missing this or that. I tried 4 other emulators and nothing seems to work. MAME can play them I think, but configuring it to do so leaves me scratching my head.
Anyone have any problems with the A7800 emulator offered in the Lair? The problem is on my end, but I'm outta ideas. Hit TAB, load cartridge, select unzipped ROM... nada.