I found the final piece of the puzzle causing Trading Port crashes. I managed to create a mod that fixes it without being a Boat Fix! For full details go here http://banishedinfo.com/mods/view/674-Jamie-s-True-Trade-Fix
Thank you!
Yes, thank you. A crash fix that doesn't mess with the boats was much needed - especially since now I can both avoid crashes and use
@slink 's No More Seeds!
Excellent work,
@JamieIdle !
Very nice. A keeper.