I don’t know zMUD at all; my opinion in the following is based on browsing its language reference. I see three options:

1. You could, of course, attempt to write a parser in zMUD’s language. Maybe I just don’t get the language yet, but it looks like this would be painful.
2. You could use the existing XSLT file and call Microsoft’s XML library via zMUD’s #SCRIPT call. There is an example of applying a stylesheet in what looks like JScript in the MSDN; VBScript should look similar modulo the syntax. Assuming that there is an easy way to fetch the page and load the stylesheet in the first place (I don’t know Microsoft’s scripting API, but I suppose there should be), this’ll be an optimal solution as it requires a minimum of external components.
3. You could install wget and libxslt and use a script via #SCRIPT to do the equivalent of Hai-Etlik’s shell script (maybe just call a batch file and read its output?). That’s messy in terms of mixing lots of rather different software, though.

By the way, I had another look at grabbing the page’s source code (rather more easily parsed than the XHTML). It’s feasible, but it would require making at least two HTTP requests and since I’m on a flaky connection right now, I’ve begun liking the XSLT approach. ^^

P.S. When you’ve got the code for zMUD, be sure to put it on the page. ;)

What does everyone else think about making a much simpler page for world exits?