Now if only we had a function in emplode to write back the contents of the database to the tags themselves

I'm not the one you want to be hassling -- in 9 days time, I'll not be employed by Rio. I'm not sure who you actually want to be hassling, though.

More sensibly, plans for the v3.0 car player software involve making it compatible with Rio Music Manager (which will require changes to RMM as well -- it doesn't currently support heirarchical playlists), which will make this stuff easier in future.