Mike- Sorry to hear about the Polly Scale flat, but also a bit relived that it is not just me! (sorry!) I have been using the stuff for years, but lately it has not been working for me at all. The satin and gloss seem just fine, but every time I try the flat it is the same thing- slightly milky and patchy too. What are you going to use now for yours? I may have a go with whatever you choose as well.