Hi Tim
I had a look (visual) and go at imaging Saturn last night between imaging Nebula.
Although my images were miserable compared to yours! It shows how much aperture makes a difference as I was using an ED80. Although visual views were very pleasing through a Meade (Model 140) 2x barlow and a Meade 24-8mm zoom EP. Crisp clear and good FOV.
However, imaging was a complete waste of time with the SPC900NC webcam, 2x barlow (listed above) and a try through both wxastrocapture and sharpcap software. Struggled with focus, size, contrast and just about everything else. Just when I thought I was getting the hang of imaging planets and just moved on to DSO's.
I too sturggled with Registax maybe I should give AutoStakkert a go too.
Excellent result keep it up and thanks for sharing!
Regards
Gav