Ok, "maybe" I haven't been very constructive either
so I decided to try this patch out. First thing first, let me say I'm very intrigued by its possibilities!
So, what I did was to construct a very simple line, and then run a short train on it. I sent it to a station and then ordered it to decouple.
In my initial consist (a locomotive and 3 pax coaches), the wagons' livery and recoloring were chosen according to the type of engine (through a callback, not livery override). Right upon decoupling, the wagons lost their engine-driven livery and reverted back to their default looks.
Now, this is not really optimal... Ideally, it'd be nice if they kept their livery as of when they left the depot. Perhaps creating a "shadow engine" would be a solution? As discussed, the only alternative to avoid this magical livery change upon decoupling, would be to clutter the purchase list with infinite wagon variants, which I don't think would be a great solution.
In any case, after decoupling, I sent the lonely engine through a couple of waypoints, and then gave the order to "couple any train". Unfortunately, almost immediately after, the game crashed with the attached error message...
File comment: error message after giving the order to couple
ng_decouple_error_0.png [67.02 KiB]
Not downloaded yet
I'm using my own trackset. Could this be the cause of the crash?
I'm also attaching all the docs created during the crash. Hope they can be useful to fix this...