Thanks for the feedback Norgg :)
I think the bug you encountered is like the one I mention on the download page which unfortunately I didn't manage to fix before the deadline. It happens when you point two beams at the same thing, and then when you move one it can 'turn off' the piece that is still being hit by another beam. Should be easy to fix though, just by moving the buggy one to another square on the board, then back again. It happens most with the teleporters since you can position them anywhere and rotate them any which way. Maybe I'll have them in a fixed position to avoid that in a future version.