-Install mod
-Open any map world
-Place down some pipes
-"Select" the pipes.

Reboot once...once...and it suddenly shifts itself to the center of the grid space. Permanently. (Until updating the mod, where it does it again...until reboot.)
I use a corpse type entity and util.table.deepcopy.
Bilka has taken a look at this and wanted me to put up a bug report. Stated he cannot repro in 0.17, but can repro in 0.16.