The hack works fine. If you are having problems with software errors it could be possible the instructions confused you or another hack is somehow messing it up.
As for the SSI include, if exec cgi or include aren't working and it is displaying the actual string itself, then I'd check with your server admin on that box. It doesn't sound like he has SSI enabled for the cgi-bin and isn't allowing you to access the files or something of that nature.
In either way, not trying to be rude.. But please work those problems out on your end and let the creator of the hack concentrate on finishing and incorporating some new features into it.
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