Fixed Now, What is this...

[SpinnerBondRX]

...

 

[Pheonixfire1011]

i think that when the user activated the pistons they went out side of the plot so the piston glitch and that is the result

 

[Zainos]

Yea that happens when someone activates a piston and does /plotme clear
To fix it just put a block next to the bugged piston head and break it, it will automagically break the bugged piston head too