I do not have access to a C compiler, and cannot be the local administrator on my machine. I don't have download rights either

You're fairly screwed then, I'd say.

First: Crypt::DES is an XS module, meaning that parts of it are written in C; it can't be installed without a C compiler. Of course, that's only a concern if it's not already included as part of your Perl distribution (Strawberry Perl includes it; I don't know about ActiveState).

Second: I'd advise against simply copying files into places to install a Perl module. If you absolutely cannot download a module at all, copy all the files into a specific directory structure as if you just downloaded and unpacked the module, and then install it the usual way (perl Makefile.PL etc).

However, I think the best option will be to bug your local system administrators to either handle this for you, or give you the rights to handle it yourself, the proper way. Ultimately, this is a social problem rather than a technical one: you've been given a task but not the tools (rights) needed to complete it. Instead of trying to work around that, make sure you're given access to the tools you need to do your job.

Good luck!