Hi David,
I meant a higher resolution image of the Cats paw. You could host it on astrobin, pbase or other similar hosting sites.
with Ha and RGB, I think Rob Gendler's tutorial is good.
http://www.robgendlerastropics.com/HARGB.html
But there are various techniques, mainly to avoid Ha overpowering the other channels.
you might want to look at PI tutorials for HaRGB or HaLRGB with a synthetic luminence channel from RGB.
Cheers