I disagree with FFF on this one. In my opinion continuing the approach was the best course of action. I'm sure that if Genghis had turned in the same direction as his PA-28 'friend' then in a few months time we'd be reading AAIB reports on the unfortunate occurance. Genghis changing direction/flight path in any way would have increased the risk. I get the impression that the PA-28 pilot did have the microlight in sight and he did take avoiding action. No need to complicate the situation further.
What I see as the problem here is the PA-28 creating the situation in the first place. As the chap was obviously not agreeable on the fact that Genghis felt he had been put in a dangerous situation, somebody needs to apply a bit a presure on him. Submit an airprox and get the CAA (or whichever body looks at these things) on your side. Don't let him use his hours or his age to bully his way out of the situation. If he was at fault he needs to be told.
D