OPTION 1: (incredibly simple)
Find the .GDB file you are using in the copy of nRoute that has the track file(s) you want and copy it to the other computer and open it in nRoute. (Hint: search the hard drive for any files with *.GDB. If there's more than one, hopefully the name or its location will make it obvious which one you want.)
OPTION 2: (pretty easy)
If you have no idea where the .GDB file is that nRoute is opening:
-Open nRoute.
-- Click on the Tracks tab.
-- Select the track(s) you want to copy.
-- Right-click > Copy (or EDIT > Copy).
-Open Mapsource.
-- Click on the Tracks tab.
-- Right-click > Paste (or EDIT > Paste).
-- Save As "Garmin GPS Database Version 2 (*.gdb)". (Critical that you save as a version 2 gdb file. The default version 3 will not work in nRoute.)
Copy the .GDB file to the other computer and open it in nRoute.
...ken...