Complex sentence: Their most recent album is "On Solid Ground" which was released on 2013 they appeared on Kid Frost's 2001 CD, "Still Up in This Shit!", performing a new version of The Notations' "I'm Still Here".
Split into simpler sentences: Their most recent album is "On Solid Ground" which was released on 2013. They appeared on Kid Frost's 2001 CD, "Still Up in This Shit!", performing a new version of The Notations' "I'm Still Here".