It sounds as if you may live across the pond. I don't know the term stempling (spell checker and answers.com don't either) but I am guessing you are referring to adding a decorative pattern or swirl to the ceiling.
US terminology - texture.
Too many questions to answer question well. Peeling paint would indicate there was grease or other contaminant that should have been cleaned before the last paint. There is nothing I know of that will fix this short of peeling off the unstuck material. Wash all surfaces with a cleaner - real TSP is one of the best (make sure it really is trisodium phosphate).
Drywall compound will stick to almost any clean sound surface. It can be dabbed on with a brush; scrunched on with a sponge, rag, or crumpled up newspaper; rolled on with a roller; splattered on with a texture gun; trowelled on with a notched trowel or skip applied; it can be knocked down or not. Practice on a scrap piece of drywall, cardboard, or sheathing to get the effect you want.