Thanks, they (Humble Bundle) should really notify if something is region locked, and to what countries. Will make sure to see what's up next time. Unfortunately also afaik there is not a way to check what region a certain key is in advance, unless I'm missing something. (Maybe just the region of your subscription?)

Read a thing about just creating a gift link which notify where it might not be able to be activated, guess that just what you do.
Well you live and learn, just another thing to deal with in the future.
In any way, thanks for the heads up!