The one week idle-time the merchant carts had had a little bug in it, and
carts did not function properly if you had to reload them at the guild after
they had been sent to the void.

Now you should not need to reload them twice, and you can reset your weeks
idletime at the guild by loading your cart, even if it's still there. It now
also properly works if the time has ran out and you are the first to visit the
cart after that.