Huh! I'm surprised people still use this.
As to your error, I assume you are using the latest version on sf.net. Unfortunately, I don't know what caused this error. It seems to be a problem with Perl. What you can try is to delete the whole "par-53495732" folder, reboot the computer and try to run it again.
By the way, if you run it without mounting or extracting a windows installation image into mount, you will get the following error:
It seems, the Windows installation wim file is not mounted in mount!