i've installed 3 or 4 different panels for the sidebar, by copying the approriate extension to the components folder. i can see them in the list of loaded libraries, and i can alter each of their setting's in the preferences window as well. But I can't add them to the sidebar at all, when i right click on the sidebar, I only have the menu entries for the default panels, ie, playlist switcher, visualization, menu, playback buttons, playback order, and seekbar. The panels in question are the album list, album list panel, and the database explorer panel. Anybody else have this problem before, or know how to resolve it? Thanks.

Most likely, the problem is that you have components for different versions of the ui_extension API (and that album list itself is no panel..)

In your case it sounds like you have outdated columns ui. Update it to version 0.1.2 available from my site. Failing that, update your panels.

thanks, that fixed it