I've observed the condensation thing every now and then. It usually goes away after a while and doesn't seem to be too much of a problem.
As for mould, I've only ever had that happen once, with a jar of Three Nuns. I have no idea how it happened, as i had it sealed up in the same kind of Mason jar I use for all my tobaccos, and stored in the same cupboard. My Three Nuns was also noticeably drier than most other blends out of the tin, so it was very unexpected.
Overall, i don't think the introduction of moisture puts tobacco too much in danger of mould. Within reason, of course. After all, safe and common methods of re-hydration include spraying the stuff with water or putting a damp piece of sponge into the jar/tin/pouch.