The "Blue tanks and teeth can push ice blocks" compatibility setting seems to be to switch CC2 ice block behavior to pgchip ice block behavior, but the wiki page lists some additional aspects:
don't melt on contact with fireballs
can't go on any terrain dirt blocks can't, except dirt
only erases dirt, not acting dirt (i.e. fake blue walls, open chip sockets)
The "Blue tanks and teeth can push ice blocks" compatibility setting seems to be to switch CC2 ice block behavior to pgchip ice block behavior, but the wiki page lists some additional aspects: