Ok, so I know this is my first bug report, but I've tried to gather as much info as I can. If you need anything else, please ask. I'll see what I can do.
Anyway,
It appears as though any caravan that attempts to get to my depot, fails to unload. It gets there. It says they're unloading. But shortly after, they just take off.
Usually what happens, is that two wagons get there. The first one gets to the center, then the second one doesn't make it all the way onto the depot. It sits one tile off. After a little while, the second wagon(I think) disappears, and drops all of it's stuff. Immediately after this happens, the first wagon leaves.
I never have the ability to trade, as they never fully finish unloading (if they've even actually started.)
Another thing to note: The depot they are trying to access is not my first one. My first one, I built underground. Unfortunately, due to another possible bug )that I'm still gathering info on), the wagons felt that there was no wagon access to said depot. (yes, I used ramps, and yes I made sure that the ramps on the first floor had sufficient clear space for the wagons to make their way down.)
So, because of that, I reloaded a save that I conveniently made at the beginning of autumn, in order to try to get an accessible depot.
I've tried with having the original depot still there as well as destroying the original depot and then building the second one. Each time, reproducing the effect.
Save file is available upon request.
[ February 21, 2008: Message edited by: Lorithad ]