I noticed this a couple months ago and just figured out how to reproduce it now.
If you build large blocks, even flat ones, such as 10,000x0.01x10,000 - the processors go to 100% and the game freezes while in the build screen within a few seconds of placing the block.
Exactly how to reproduce:
-Enter creative mode
-Jump to empty sector
-Found a new player ship
-Modify the root block to double size, twice
-Select trinium glass from the menu
-modify stats to x:10,000 y: 0.01 z:10,000
-Place glass with flat side flush on root block
-Wait a few seconds and watch as your processors rev up and then the computer freezes.
Computer is unresponsive, end program and security functions are unable to regain computer control.
I am using a NVidia 1050 with 8 core I7 processors, this is/was the very best shelf stock computer.
Smaller block sizes freeze computer as well, on my laptop I tested 5000x5000x0.01. First time this occurred, it was stone blocks, so it doesn't seem to be just glass.
~Zhrocknian, 800 hours in game.