Ah very nice to hear, I hope you have had a good time!
I would love to play around if you had an old version of the double bogie setup still somewhere to see if it could work (or is it in one of the older downloads?)
I also noted the movement in couplings for most cars was more than I thought and adequate in almost all circumstances. The derailings were mainly due to the same issue of overhang / distance between the point of articulation on the bogie and the connection point. It only tends to occur on those double bogie setups and locomotives with longer bogies or overhangs. It wouldn’t be realistic but if the bogie’s articulation was unsymmetrical and closer to the connection points it might help, or tweaking those couplings on offending vehicles.
I am interested to see your solution for containers and what (if any) compromise has to be made. I didn’t look very far into other vehicles that carry containers but for my use case I also added support for 2x 20/25’ containers alongside the middle connectors.
I also found out why you made the set 5 cars long.. while I determined my yards would work better with sets of 7 it can be difficult to work out which vehicle is selected past the 5th car. Not to mention when you have 2 locomotives, 2 sets of 7 cars each stacked with 2-4 containers, that could be well over 50 connections! I don’t know if it was your intention to support long configurations but performance also struggled with more cars attached, though fs was clearly never meant to do any of this in the first place so I don’t blame you or anyone for issues like this. Keep up the good work and I wish you all the best with your marriage!