is there much difference between this 'made and developed for sticking plasterboards' stuff and gun grade foam used for everything else? just seems a bit of a 'repackage the same product under a different name and charge more for it'...
not the diy stuff though, that tends to be high expansion...
if its anything like ordinary polyeurathane foam a good tip is to wet up the substrate slightly, it gives a better 'cell structure' to the foam, expands less, cures slightly quicker and is more dense..
ive had some 2x2 with a masonary screw in either end before today (where ive been dabbin and the boards have been left stood up overnight and bowed), the ones where you dont need a plug, just a 6mm sds drill bit, put the screws in the timber, use the screw ends to mark the board, drill through the board into the wall and wind the screws in.. it'll pull the board flat across the length of the timber..