: GSview 5.0 generally requires Ghostscript versions between 7.04 and 9.99 . Newer versions of Ghostscript (9.53+) changed their versioning format, causing GSview to report a "Wrong version of DLL" error.
Historically, users purchased a key to remove the nag screen. However, Ghostgum Software has largely ceased active commercial operations for GSview 5.0. Gsview 5.0 Registration Key
A newer (though also older) version maintained by Artifex, though it is a different product from the Ghostgum 5.0 version. : GSview 5
: Supporting software developers by purchasing licenses contributes to the ongoing development and support of the software. Gsview 5.0 Registration Key