My guess is that the install command of your unix is incompatible with the assumptions of the module author. As the Makefile.PL is full of hand-rolled code, it seems that the author is not fond of ExtUtils::MakeMaker and the mechanisms it provides for installing files.

A possible way out could be to avoid the configuration overall and do the copying manually, as hinted in the INSTALL file:

You can override where the configuration file will go
by specifying the SYSCONFDIR setting.  /etc is the default.
Or to avoid installing a configuration altogether use
"make NOCONF=1 install" instead.
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