Complex sentence: Lambert has continued to work as a freelance producer outside of her own company, having produced the popular BBC One comedy-drama series "Jonathan Creek", by writer David Renwick, ever since taking over the role for its second series in 1998.
Split into simpler sentences: Lambert has continued to work as a freelance producer outside of her own company. She has produced the popular BBC One comedy-drama series "Jonathan Creek", by writer David Renwick, ever since taking over the role for its second series in 1998.