BigLev

I'm sure this has been asked a million times and I am somehow missing it but any help is greatly appreciated. Anyway, I have launchbox/Big box and everything runs fine, except for MAME. I have my ROM set and I go to install it with the MAME Full set importer and all goes well. I have done this with zipped and unzipped files but the result is the same. I can get all the media so it all looks nice but as soon as I go to launch the screen goes black and then I see the list of games again. My arcade has been deleted so I can start fresh with any advice I get from you guys. Thanks.