Complex sentence: After the demise Kim Larsen would go on to become a very successful solo artist; his album from 1983, "Midt om Natten", is the best selling album in Denmark ever.
Split into simpler sentences: After the demise, Kim Larsen would go on to become a very successful solo artist. His album from 1983, "Midt om Natten", is the best-selling album in Denmark ever.