Am I right in understanding that you want to save the version number of a module, outside of that module, in a program "that actually calls all other perl scripts that make use of this module"?

I think that is a very bad idea. A module should be (as much as possible) self-contained and know its own version number. If somehow other scripts need to know the version number of a module, there should be a variable or method available in that module to provide the version number. Look at many modules on CPAN: they have their version number stored in a $VERSION variable.

But perhaps I misunderstood you or perhaps you have a very good reason to externally save the version number, but then you will have to explain it more clearly.