My plasterers will not use Diamond base, their method of choice is Imperial Basecoat and Diamond Finish w/ a little retarder to slow it down some. The Diamond Base has proven to be fairly inconsistant setting time wise. One piece of advice from me and I am a proficient hawk and trowel taper, Veneer plaster is a PITA to learn, timing is everything with it, Build a couple of Mock walls and practice there until you think you have it down and then some more for safety, because once it goes off you re stuck there is no going back, to tear it off you replace the Blueboard too!!!:furious: On your finish, lay it on about an 1/8-3/16"smooth , once it starts to set get your pool trowel out and some water and slick it out from there. Remember you cant sand it so watch out and good luck.
Trace

P.S.
Remember to start in a corner and finish the whole wall it has a tendency to flash through paint if you stop mid panel.