I have had some interesting experiences with Storable, in the form of data which, once frozen, could not be thawed!   This was on an AS/400, and it was very data-specific, and I do not know if it was a momentary bug in whatever-it-was version of the CPAN module.   But as it was, I had to quickly scramble and store the data in the database in a different format.   (Fortunately, this was an SQLite file that didn’t have to be shared with anyone, but the occurrence of the problem surprised me greatly, nonetheless.)