registax help

Hello,

I would be very grateful if someone could help me with Registax. I used
Registax (v3) for a long time on planets images and never have much
problems. It seems to me that almost any settings to start with will end up
with properly aligned frames!
Howeevr, I recently bought a Coronado PST and try to image the sun surface
(with a Toucam Pro attached). The rough avi file is not very contratsed, but
it seems to me that there are enough visible details to make an alignment.
But whatever settings I choose (FFT and quality filter, alignment box size),
I just cannot get it to align the frame properly. I put together some screen
grabs of this and put them he
http://www.gogo.me.uk/registax_problem.html
so you can have a look at what I'm talking about.
Any advice would be more than welcome!

Many thanks

Philippe