It appears you might be using your computer operating system instead of using the BBMO (BeatBuddy Manager Online) to manage your content.
Since the content is proprietary, it requires the use of the BBMO to get beats, songs, pbf folders and drum sets onto the SD card so that the BeatBuddy (BB) pedal will recognize and play them.
Your starting point should be to read the BBMO Manual and then start to use the BBMO which requires a browser—the manual identifies which browsers support the BBMO.
Since you may have already corrupted your SD card, you might want to delete all of the content and then copy the Default Content 2.1 back to the card and then pick up with the BBMO.