"Getty" wrote in message
...

"Mike Dobony" wrote
but only over the old, smoke-covered
walls


There's you problem, as already mentioned by _xrongor_. You don't
prime/paint or use mud over dirty walls, you skipped the prep work, now
you're paying for it.


That might explain why it came loose, but not why the set compound became
wet again. This is not cheap drying compound, but setting type. I have
never seen setting type compound become soft again.