Complex sentence: Lennon sang with David Crosby on his solo album Thousand Roads, and also performed vocals for the song "Suspension", which was the main title of the movie and TV series versions of "Buck Rogers in the 25th Century".
Split into simpler sentences: Lennon sang with David Crosby on his solo album Thousand Roads. Kipp Lennon performed vocals for the song "Suspension" which was the Main Title of the movie and TV series versions of "Buck Rogers in the 25th Century".