We are traveling from Paris to Sarlat via Libourne. How much time do we need to allow for train connections?
I've never done it, but whatever ticket they sell you is going to work. Libourne is a small town with two tracks and a shrimpy station. Two to three minutes? If the schedule shows much more than five minutes of gap, it's bound to be due to having to wait for the other train to arrive.
To save precious tiome on the rare occasions we had to change trains on our recent trip to Germany and France, we made sure we were out of our seats, bags ready, standing near the exit, when the train arrived at the transfer station.