I love the supply wagon and the Skirmish option. Both are useful but not gamebreakingly easy to use. The extra challenges make the game different and much fun. The skirmish option seems to work fine, it is hard to predict casualties but that is very acceptable.
The wagon is more difficult to put to good use. It can be ambushed, but it brings in lots of extra money and less hassle going back to town all the time. I even send my prisoners along with the wagon thinking they will bring in some money... I ran into a strange issue, perhaps a bug. After I rescued the cart from a bandit attack, it continued to the target city. Later upon return it tried to rejoin but it is treated like a hostile unit. Then the hero I sent along is duplicated (present both in my party and with my wagon). The cart keeps following me around and trying to rejoin but failing. Finally I escape from the stalking wagon by cheating Shift clicking in cheatmode. My cart is ambushed and lost. Now, the hero returns to my band and I get a missing object error. After this I cannot build a new cart.
Does anyone have a suggestion how to fix this?