Looking good Baz, thats the best way to learn by experimenting.
I always take notes when experimenting so if it turns out really well I'll know what I did.
Great work Baz.
Get your self Deep Sky Stacker do 10 of what you have done..and a dark frame..you will be very happy.
Nice round stars..thats all you need ..now get some time by doing hepas and stacking them.
I have been stacking 30 x 30 seconds for acceptable results..just track as long as you can keep those stars round and then do it as many times as possible and stack the lot.
Great stuff.
alex