Can I Combine GPX files in Microsoft Streets & Trips?
I have two routes planned in two separate files. If I export each of these to GPX files, can I import those files somehow into a single route? The second route is really a continuation of the first route. Thanks.
Well, technically, you cannot combine two (or more) GPX files within S&T. However, you can in Tyre and then import the combined GPX file thereby created into S&T.

Tyre is a neat little free program (free that is if you don't mind various prods to pony-up with some Euros) that can be downloaded from www.tyretotravel.com. Even once you have that program, it is not obvious how to combine multiple routes so this is how I do it.

First, open your GPX files in Tyre. You should notice that there are multiple map sheets (like Excel worksheets) representing each file you opened. That is neat in itself but not quite the whole schnitzel if you want to combine. Therefore, what you need to do is select all the waypoints from the second, say, route using ctrl-select and copy them all at one time (ctrl-c). Then open the map sheet for the first file and go to the waypoint list and select where you want the previously-copied waypoints to be inserted. This is probably at the end but it does not have to be. Now, paste those waypoints in using ctrl-v. You have combined the two files. You might want to take a close look at your work product to make sure it is exactly the way you want it before saving it as a new GPX file and importing it into S&T.

One of the very cool features of Tyre is the ability to virtually-drive your route either in road map or satellite view. It is sped up quite a bit (I have achieved 269 MPH on a German Autobahn) so you do not die of boredom as your route unfolds.

It also works for disaggregating waypoints. For instance, suppose you created a long multi-day route that might be a bit cumbersome for actual in-vehicle navigation and you would rather have each day on its own discrete route file. Using Tyre, you can select and copy only those waypoints for each day from the whole-route file and paste them into individual day GPX files which you would then import into S&T.

In any case, Tyre is a very useful addition to any serious road navigator's arsenal of tools.
Thank you, I will try that.
Thanks for the tips SpadesFlush. Never really attempted to use Tyre like this. It works pretty good although once I'd pasted together a 1900 mile trip and sent it to a Garmin Nuvi 3597 I got the message that the Trip could not be calculated so I had to split it into 2 small gpx files before the Nuvi would place it in Trip Planner.
You are welcome!

The one thing that gets lost in a S&T -> Tyre -> S&T translation, however, is any scheduling constraints you may have imposed.

Your Nuvi experience probably related to capacity of the Nuvi rather than of Tyre. I have found that Tyre will simplify large GPX files by reducing the number of waypoints arithmetically. For instance, if I try to open a GPX file that has a long GPS trail (which will have waypoints taken every second) Tyre will decimate the data.
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