Ah yes, the unfortunate "void" bug. The game was checking if there is another object at the same location in the other reality. If there is something (npc, barrels, etc.) it does not allow the switch, but the state isn't reset entirely (last minute changes..) and the next time you want to switch realities it will place you at the opposite offset, placing you into the void. I fixed this bug (among others) and will upload it once uploads are enabled again.
Thanks for playing and I am sorry for the inconvenience.