There's a new music feature on Roqbox: now, you can create music albums, consisting of previous tracks you've uploaded as well as new tracks. Albums can have their own cover image, and any new tracks uploaded to an album automatically receive that cover image as well. You can move tracks between albums freely, as well as return them to your profile.
Note: There is currently a bug preventing the album credits appearing on the public-facing page. You can however still save & edit the album notes and credits through the web UI without any issue. I am pretty certain I know what is causing it so should be a pretty quick fix, whenever I can dedicate some time to it.
Also, Happy Halloween!