good to know I’m not the only one who keeps myself entertained with retropie at work ha ha. source folder is the main roms folder. Basically the source is asking for where you are storing the roms that you want to rebuild. so in your case your source would be roms, and the destination would be final (so after its done building your rebuilt roms will be placed in the final folder). just to clarify though a .dat file is only a database file that clrmamepro uses to rebuild the roms- after its done rebuilding you no longer need it.
