Similar problem, column browser disappears when switching between modes. When I re-enable it, it no longer shows the Artist/Album, but instead shows Genre.

For me this happens when I use "Find more from same folder (Library)" and then switch back to my Music Playlist.

There appears to have been a bug reported back in 2011 about this as well, that was determined to not be reproducible at that time (http://www.mediamonkey.com/forum/viewtopic.php?f=7&t=61922).

http://www.ventismedia.com/mantis/view.php?id=10628

If different tabs have different number of columns in the Column Browser (Art&Details view) when you switch between the tabs, the order of columns gets messed up in the tab with the bigger number of columns.