Hi folks,
OK I got a palm sander and tried to sand the paint back to the plaster but it just doesn't seem to get through this stuff and there is about 6sq/m to get through.
Any ideas of how to remove or paint over?
Just scrape or sand off all the loose/flaky bits, so you have a hard, smooth, non-flaking surface to work with (irrespective of whether it is bare plaster or not). Then Gardz it (twice), then paint it with a suitable finish for bathrooms (e.g. eggshell).