I really did enjoy this class and learned a great deal.  Even though I've used Affinity Designer for some time, I've shied away from Affinity Photo.  The only trouble I had was with the Separation filter.  What I saw you do in the video, I never accomplished.  I got the high/low layers but when I would do any adjustment on the high layer, it just made the brushed area super bright as if I had the "add" layer mode selected -- but I didn't.