When all of a player's settlements are moved away from adjacency to a location, that player loses the associated action tile.
There's no specific mention in the Marshland rules, so I'm guessing "no", but does a player lose the bonus tile when all his settlements are moved away from one or more of the corresponding locations?
It's in the spirit of the rules that you do lose the bonus ability. I believe you that the rulebook does not say so (I don't have it yet).
If a player loses a Temple tile between activating it on one turn, and taking the mandatory action of the following turn is the effect of the Temple still completed on that following turn? I'm guessing "yes".