Complex sentence: Their first album,'(named "Klaatu" in the US as Capitol Records' execs felt the original title was too obscure) was released in September 1976 in North America to moderate reviews and found itself stalled, sales-wise, by Christmas of that year.
Split into simpler sentences: Their first album,'(named "Klaatu" in the US as Capitol Records' execs felt the original title was too obscure) was released in September 1976 in North America. The album was met with moderately positive reviews, but found itself stalled, sales-wise, by Christmas of that year.