I have always been disappointed how the BBC only released the first three Naked Video series on DVD. I remember seeing Naked Video on Paramount in the mid-90s (I wasn't really old enough to remember most of the original showings) and there is a hilarious sketch in either Series 4 or 5 where Gregor Fisher is playing a weather forecaster in a science lab, saying "all these people like Michael Fish and Francis Wilson are just amateurs. To forecast the weather properly you need a cock" - and he put a large weathercock on the table. He then says "you also need a chopper" and he puts one of those garden windmills on the table with the man chopping the tree.
Was the actor who played Siadwell gone from the last two series? I know there is a scene at the end of Series 3 where Siadwell has died.