"other point to point tickets going from Munich to Kehl to Colmar to Strasbourg" "The reason for backtracking is a hotel has already been booked in Strasbourg. I just thought going to Colmar first and spending several hours strolling around the Christmas Markets and then heading back to Strasbourg for the night and spending a full day roaming the streets and Christmas Markets."
OK, so about this one-day, 7-8-hour series of train rides... If you travel via Kehl to Colmar, that means you'll stop in Strasbourg between Kehl and Colmar. Perhaps you can arrange to drop your bags there during this stopover. If that's what you hoped to do, be sure to specify Strasbourg or Kehl as a stopover on the way to Colmar when you check schedules. If you don't do this, you will pull up schedules that take you to Colmar via Basel (the more usual routing) and you will need to find a place for your bags once you reach Colmar.
You have 2 nights planned in Strasbourg, right? I would suggest an alternative that breaks up this train travel a bit more evenly. Unbook Strasbourg - then when you leave Munich, take the 5-hour train ride to Gengenbach, just east of Offenburg, for a 2-night stay. Specify a routing via Donaueschingen, and the train will take you there via the scenic Black Forest Railway line through the Black Forest. Gengenbach is Christmas-card-photo perfect - Gengenbach's town hall is made up like an advents calendar; the windows are opened daily at 18:00. The Christmas Market is open daily.
The next day, your outing - Gengenbach - Kehl - Strasbourg takes only 1 hour; Strasbourg to Colmar is only 30 minutes more. So about 3 hours of train travel that day starting and ending in Gengenbach.
Tickets:
Look for a saver fare for Munich - Gengenbach (or use a railpass day.)
Outing to Strasbourg and Colmar: Round trip between Kehl and Strasbourg: cost only €10.40 with the "Europass 24 hr Mini" - a daypass you can buy at the station. It can also be bought online HERE. Round trip between Gengenbach and Kehl is free with the KONUS card (guest card) your hosts in Gengenbach will provide. Then you have to pay only for the Strasbourg - Colmar round trip on top of that (unsure about cost but should be minimal.)
This brochure in German and French explains the 24 hr mini pass.