My method.
1 combine at least 3 of your raw darks (median) do not convert to colour, use the result as your subtractable dark frame.
2. Take your light raw subs and do this to each in this order Subtract dark - convert raw to colour- make pixels square-colour balance.
3. Now stack all the colour subs.
If someone thinks this is wrong please let me know but it works fine for me.