Thanks for the link update.
I'm not sure it matters which way 'round you do it. I've created a couple of new Windows 7 systems and then installed nRoute on them. It worked just fine without any messing about with drivers. I've also upgraded an existing Vista system that had nRoute installed on it. After the upgrade to Windows 7, nRoute continued to function happily without doing anything to the drivers.
I suspect ... and this is just a guess ... that the newer USB drivers from Garmin's website simply support some of the very latest GPS receivers. If you don't have one of their very latest, it shouldn't be an issue.
Or, it's possible that the new ones are certified for Windows 7 and the old ones aren't, but might work anyway.
...ken...
Thanks for responding! I agree with you!! And, to comment on your theory, I think it started with using drivers from v8 which were way too old for my system. I just had the latest ones off of the website handy.