LONDON — Sean Kirkegaard, former founder and head of FremantleMedia’s format think tank Ignition, is joining producer Presentable as head of factual entertainment and development.Presentable, makers of Channel 4’s “Late Night Poker,” has signed Kirkegaard to increase the company’s commissions and expand its genre base. Kirkegaard also will use his international contacts to build relationships in Europe and the U.S. Presentable, based in Cardiff, has received funding from C4 to establish a base in London and build a library of formats with international appeal. Channel failed to reach its regional production quota last year. Chris Stuart and Megan Stuart founded the company 10 years ago. It produces factual and entertainment content for C4, the BBC and ITV1 Wales.