There is already a bug "missing inc directory", which contains the aforementioned error message.
next update: I just noticed there is an "unauthorized release" 1.1.5 by chromatic.
I am behind a firewall and therefore using a "Minicpan" which is obviously outdated.
Will try to check with actual CPAN and get back with the result later.
on a fresh strawberry didn't have the Module::Install missing (I added that info to rt://28125
still needs attention, but might be a problem in PDF::API2