Complex sentence: The aim of the club was promotion straight back to the Regionalliga, the men in charge of this rapid promotion challenge were Adnan Kevric and Roland Seitz however Seitz left to take over at Paderborn within just a few days of his appointment.
Split into simpler sentences: The aim of the club was promotion straight back to the Regionalliga and the men in charge of this rapid promotion challenge were Adnan Kevric and Roland Seitz. However, Seitz left to take over at "SC Paderborn" within just a few days of his appointment.