medstrax, I've encountered something similar. On single-player, custom maps, especially if everything is very densely packed, and the author saved on free spaces, sometimes this unforeseen issue occurs where neutral creatures spawn at the beginning of the week in a location where it becomes impossible to pass without cheating: for example, one cell for disembarking from a boat, and there, as if on cue, are some gremlins! :( Moreover, the probability of this is not that small: it is all the more likely the denser the map is and the longer the game lasts; accordingly, there are few free cells, and eventually, newly spawned neutral creatures occupy a critical position for passing.