same here. frozen after dragon fight wolrd one
EDIT - Fixed.
so when i got the game, i installed it directly to my hdd thru my pc using wbfs_inteligent_gui_v6.
i did not burn a disc.
i played up to the final boss on world one.... no music during that fight, and after beaten, black screen after i got the grand star....
tried other loaders, same thing.
so i took the ciso into Wii Backup Manager, and converted it into an iso.
after that was done, i opened WBFS Manager 3.0 and deleted the "smg2 more.ciso" and added my new "smg2 more.iso"
booted the game, flew thru the level, had background music during the boss fight, got star and moved on to a new world !
i hope this helped the few of u that are running into the same issue.