When trying to install stock Ghostscript PDF print diver on a 64-bit Windows the OS requires the print driver to be signed and the installation fails (Add Printer dialog cannot be confirmed). You can disable this OS protection feature with a special system restart but the setting will last until the next restart.
Here is a faster way to install the printer on x64
So following instructions in this stackoverflow answer I managed to produce a signed ghostpdf.cat for Ghostscript PDF print diver. Our code-signing certificate will expire on Aug 29th, 2014 but I hope to have the time to update the certificate by then.
Enjoy!
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