I got some advice from a co-worker in another department and went out to the Mercury Support Knowledge Base.  I used a GetROProperty command to get the encoded URL and feed it back to the script so that I always have the URL created by the run.  I've also figured out how to parameterize the starting URL so I can change country, language, etc for our international purchase paths.  I'm feeling very good about my progress with QTP and VBScripting right now.