Automatically upgrade buildings by hand or with construction robots.
Providing the player with new tools or adjusting the game interface, without fundamentally changing gameplay.
I've just downloaded the Mod, and setup the belt from yellow to red. If I choose the upgrade builder, and left mouse over a belt, everything upgrades as expected. If I Alt-Left mouse, nothing happens.
So, what am I doing wrong?
Shift key to upgrade with robots.
