I would take your new install that is working and move over the all the data files from the previous install to it. Only do the files in folder UNDER data, not the files in the root of data (Settings.xml, BigBoxSettings.xml, etc). Those files have all your platform, playlist, and game information in them. Try to open Big Box after that and see if it works. If not you may need to do it one at a time and see which breaks it as you could have a potential data issue causing the error. IF that works you can start migrating your media back over (Images and Videos folder).