Thanks Ric and Rob. Not being used to RGB, colour was a struggle, despite Jases protest, his M51 was a handy reference.
I had trouble with the satellite galaxy dust lanes, thought I was over processing until I just found this by Ken Crawford, it really is an odd shape.
http://rdelsol.com/Galaxy/M51_LRGB_FC3.jpg
Wouldnt you kill for an image like this ;-).