I never used BrawlBox for my BRSTM's. Just use Dantarion's Brawl Custom Song Maker GUI. It runs into errors sometimes but it works pretty well and it displays all the names of the the custom song, the song it goes over, and what stage it's on. Here's a link to the Smashboards thread.
Link:
http://www.smashboards.com/showthread.php?t=241578