Looks like there are issues with Set Specific Tile Cost action.
Here is an exemple on my game, if I add additionnal TileCost of 99 at the position of the ennemi, the comportement is really weird for no reason :
If, instead, I just change the tile at this place by another place with the same tilecost, 99, it's working.
I've also notice some others strange behavior with this Set Additionnal Tilecost.
I hope this can be fixedone day, this extension is really incredible.