So... you just answered your own question or do you also want some reaction of others?
Lets asume the latest:
The quick drive function gets trains out of a pre-made list. You can add trains to that list by opening a session, add some trains+cars to a piece of track and then save that. In other words: Go to the last tab on the right side of the screen in surveyor. Put rolingstock on track, go to the 2nd option in that tab ("Train Mode (C)"), click on the fork-like icon ("Get Consist (G)"), save the train.
Now you have that train in your quick drive list.