I was talking about this with someone on IRC last week, the problem is advanced inventory queues up a bunch of actions (mostly in an attempt to be friendly), and only “charges” you for the moves required at the very end. When that happens you’ve spent all your moves for the next 10, 20, 100+ turns already, and you can’t do anything until your moves go back positive. Meanwhile that dastardly Mr. Cougar has all the turns they want to feast upon your entrails.
The difficulty in fixing it lies in the fact that you have to record this backlog of actions in a way that will be stable across turns, and most of our item references aren’t stable if you start adding and removing items from the same tile.
Probably the simplest option is to have advanced inventory stop trying to be so nice, just have it actually move items around immediately, and charge you for it immediately. When you run out of moves, your turn would end, everything else would move, and the advanced inventory would pop back up automatically, you probably wouldn’t even notice anything. If you’re moving a lot of stuff around though, you’d get the usual warnings and such if monsters approached or you took damage.