First off, whenever you have a problem that results in a crash, you will get the best help if you include the log file. As for your error that you are describing, it could be nothing or it could be something. Depending on your system, it can take a LONG time to build the list. On slower machines, I have heard of it taking 30-45 minutes. On my machines, it usually takes on the order of 20 minutes. When it's building the list, it will give you cues to tell what's going on though, so I wouldn't consider it a 'hang'. If you watch, the thing that takes the longest is verifying the roms. It will give you a number to show how many it's gone through, so as long as it's changing, things are going ok. The things to check are: * paths (roms, mame.exe, etc.) * same version of MAME and roms * make sure you are using a modern version of MAME (older versions used a different format for outputting lists) * make sure that if you are not using the official MAME release, that your version is compatible with MAME's verify roms capability. If you don't know, try using the official release...