It may be I'm confused by your situation. If you are writing some software which you are going to sell, and your software uses some modules from CPAN, it seems to me this is not a problem - unless you want to package the CPAN software within your own release.

I seem to remember other discussions where people realized that if your _customer_ is installing CPAN modules to satisfy prerequisites stated in your products README, and then your software is installed, then they (the customer) is simply using CPAN correctly, to upgrade their Perl installation. You aren't involved at all in that transaction.

Now if you want to check over the individual module licenses yourself, so that you can tell the customer that there are no restrictions on _their_ use of the modules, that seems a nice thing to do. But, all, please tell me if there are any modules out there that say you (the customer) can't install them if their company name starts with 'M', are incorporated in Papua New Guinea, or are just too tall.