Hi,
I can only tell something about tin figures!
If you keep tin figures too cool, chemical reactions can occur on the surface of the figures, corrosion takes place and forms the so-called tin plague.
As I know, the limit is 13-14 degrees Celcsius, in the positive range!
Please, keep the figures warmer.
And a piece of advice to all collector friends:
If you are offered tin figures (in a circle of friends, neighborhood or on ebay), where the old owner says that these figures were on the attic or in the basement for years, then you better stay away!
Most of these figures have the tin plague.
BG
Christian