I don't know where the "D:" came from. You should have something of the form:
<a href=/cgi-bin/texis.exe/webinator/search/>
The above is a virtual path comprised of 2 parts. "/cgi-bin/texis.exe" is
the Texis Web Script interpreter and "/webinator/search" is the path
to the search script relative to the web server's document root.
Running just /cgi-bin/texis.exe should give you a copyright message if it's
installed in a CGI enabled directory. If you get "404" errors, you've installed
to a directory that doesn't exist in your web server. If you get a "file save"
dialog, or some such, the directory is not CGI enabled.
Version 3 will have a web interface to the walker.