Hi, I have installed onto newly plastered walls/ceiling: 1. plaster cornice 2. polyurethane (plastic-type) panelling on the ceiling. I have almost finished putting them both up and filling on the gaps. I am now about to start painting the ceiling/walls. My question I shall be using Dulux Trade Supermatt (diluted 30%) to first prime the walls and ceiling. However, should I use the same paint to prime the cornice and panelling or do I have to use PVA solution or similar, first? The panelling on the ceiling has its mitres filled in with coving adhesive/filler and the corners feel a little fragile, ie. if i take a screwdriver I can easily start scraping away and damaging the corners that were finished with the filler. Surely I cannot paint the panelling while it is in this condition? It needs to be stronger, this is why I was thinking about using a coat of PVA solution, first. Thanks.