Xbox Series X Formation Designer Issue (since Tsw 6)

I know this probably won’t get fixed. But wanted to spawn in the stamford trash cars for a train. I found that I could find them in the list of spawnable items only as the first part of my formation. After selecting them the game sorta soft locks itself. Cant spawn anything else in on this formation. Cant add this custom formation on to another (pictured in my screenshot). Would be nice if this was fixed. Unique railcar not used a lot.