Very very nice Paul, one of your best I think! And thanks for finding such a gem of a target too. Now I'm inclined to have a go as well, but it already seems to be the flavour of the month...
Very interesting about the diffraction spikes too, I noticed exactly the same in my 120 hour CenA image. I wondered what on earth could have caused a second set of faint spikes perfectly ortogonal with the frame (my normal spikes from the spider are at an angle). Must be the microlenses as you say, and it apparently only shows with sufficient integration time.