Todd,
I think I agree with David - as I look back on what it would have been like for me if I hadn't created a global user folder up front, I'd probably be saying to everybody, 'I'm locking my door, I have a ton of selective search/replaces to do and then run the app from two different terminals. Give me a day or two'.
I can't speak for your specific situation, but if you have C:\TEMP hardwired everywhere, it shouldn't be that bad - and at the end, you have a solution.
Kevin