If you create an infinitely recursive structure - that is, save a structure which includes a load block and power source that will load the same structure - the game will crash with a stack overflow. I realize this is expected and the player's fault (my fault, in this test case), but considering it's possible to accidentally create these infinite recursions, and there isn't even one second between the first load and the crash, it seems there should be some protection in place to prevent this (like a maximum number of structure loading method calls on the stack before no more are called). It'd be much better to have structures stop spawning in these cases than a full-blown crash.