Your advertisement on the Truimph Owners Club website says five or six days away. Your post #7 says three nights in Freiburg im Breisgau (bottom end of the Black Forest) which translates to a minimum of two full days in the Black Forest. That, if your total holiday is to be five (not six) leaves either:
A. One day to get to Freiburg im Breisgau and two to come back, or
B. Two to get there, one to come back
Are you sure you are set on six days? I guess so or you’ll be doing a whole chunk of motorway to either get there or come back.
Now to try to help you:
1. What time do you roll off the ferry / train in Calais. 7 am? Noon? Two in the afternoon?
2. What time do you need to roll back on?
I ask this only to determine how much of a day you have available on the first and last day. Often on this site we discover that bods don’t plan on arriving until noon and want to be in their hotel by 17:00 having stopped for an hour for lunch.... and still expect to travel 350 miles in four hours having avoided motorways, an average moving speed of 87.5 mph on the scenic (green lined) roads someone has told them they must use.
This is the Kurviger route between Calais and Freiburg im Breisgau, 442 miles door to door
https://kurv.gr/2yKju
As you can see it misses out the Ardennes and the Mosel / Moselle valley; that doesn’t matter as it sort of gives you the start of something to work on for your return through France. 442 miles over two equally spaced days is 221 miles a day on the D roads of France, perfectly doable for a modestly sized group, leaving at 09:30 finishing at say 17:30 with a morning coffee, a fuel stop and lunch. Run your finger along the blue line to about halfway and you’ll be somewhere around Rethel. There is no Ibis in Rethel, so look at places somewhere around there where there is one. You are now starting to cook on gas and your return route is sort of working itself out and you’ve not touched a motorway.
Next the way down....
You want to ‘do’ the Ardennes and the Moselle? The river flows roughly Epinal to Koblrnz so you need to decide where to join it.
Somewhere around Trier / Luxembourg / Metz I guess? Now, how do you join Calais to say, Metz via the Ardennes and how much motorway do you need? Time to cheat again by going to Kurviger and using a touch of imagination, all the way from Calais to your chosen stop off point at the bottom of the Black Forest.
https://kurv.gr/1yg7f
That is give or take 500 miles, no motorways. Still doable in two days for sure, depending on your answers to my questions above. I did it all on an iPad, without touching a paper map; it really is that easy. You can export Kurviger routes as a track (it’s neater than a route into BaseCamp) to start your work from. In short, you now have a Kurviger gpx trace, which is near enough what you asked for. See the post I mentioned about not trusting Kurviger to throw in some silly ‘twisty’ bits just to pee you off and make you the laughing stock of the gaggle of happy Triumphalists following you down some ridiculous goat track.
Want to join the river at Trier instead? Easy, insert Trier into the top bit of the route list in Kurviger after Bastogne. You are now up to 538 miles. Thirty miles on D roads is about an hour if you don’t dawdle. It does illustrate (which is what people forget) how adding in places in between A (the start point) and B (the end point) extends routes and therefore time. As you can see it’s about 100 miles further than the return route.
https://kurv.gr/c4u1T
Now what to do? These routes all exclude motorways. But we have no idea how long you have really got for your two ‘two day’ travels A to B and back to A.
I’d suggest Calais > motorway, you can see the A26 running parallel to the non-motorway blue line from Calais, which is why they built the thing > Cambrai (to get you cracking along and as you have decided northern French roads are all no go) > D / N roads across Belgium / the Ardennes to pick up the river Moselle > then near enough follow the blue line along to complete the total two day jaunt. Zoom in and out a bit / look at a map to see if it suits you exactly. Where to stay? Easy enough for you to work out, based on which route you take and how long you’ve got on day one / want to take on day two. A good place to pinpoint as a rough start is logically about halfway along the total two day route. But hey, it’s your turn now....
PS If you go, as you may well do, to Nancy. Take the motorway around the place. It’s a real grind getting through it.