Chris
Deep Sky Stacker is one of the most popular stacking freeware world wide with great support and information on how to use it
Go to
www.deepskystacker.free.fr
I load my Canon raw (CR ) files , darks, flats etc into DSS , all my settings are preset with the exception of a couple like registering and stacking parameters and Star mass detection
It’s so easy and I get great results from a stack of 10 to 100
It has some post processing tools at the end but I don’t use them , my stacked image is saved as a fits file and then loaded into Startools for post processing
My base DSS settings are customised for a Canon DSLR which is great
Martin