Thought I'd share this tip from the plasterer that we have in at the moment. Having gutted the extension of the house and dealt with all sorts of problems (dry rot in joists etc) we've finally finished and were ready to get it plastered. We're re-wiring at the same time, so we'd chased cables into the walls and covered with plastic protective stuff which is of course quite shiny. Oh, the walls are block and render by the way. So anyway, the tip is, to get the compo to stick properly to the shiny plastic and the smooth bricks that are dotted about, mix up some PVA, sand, cement and water and just paint it on - compo should stick like magic.
Well I thought it was a useful tip anyway - never seen it mentioned anywhere else before (and am a long time lurker ;).
Phil