Thank you, kb. I've used this, too. It works well, but the kind I've used also expanded a lot, even when I wiped it even with the surface. Did your do this? (Mine was tan-coloured).
I think maybe 3 coats of the drywall stuff will work, but then I am wondering about the difference in wall texture when I paint over it. Yikes. I'll try to get a Home Depot person where they got the insulation and find out. Either that, or I have to pay for it. Can't do that.
If I find out, I'll post it.