This is obviously for other beginners like myself. Hopefully I can save someone some head-scratching…
He original post (below) detailed how my Ardumotor shield was not properly driving the motor I had connected to it - the motor would only go one direction. I thought I had tested all the connections, however the issue turned out to be bad connections between the stackable headers on the Ardumotor shield and the UNO. The Ardumotor shield overlaps the USB input connector ever so slightly, so you can push the shield pins all the way in.
Solution was to use a second set of stackable headers. Ardumotor working exactly like it should now
Grazie!
Jon smiley-cool