COGs are blinded from constant work in dark caves with super bright lava. It is almost impossible for them to spot the player unless they are fired upon, or damaged in any other way. If that happens, they will charge in the direction of incoming fire and fight back! So be careful!
The paint job design is applied to the starter drillship you get from Captain at the begining of the game. The Design grows with the drillship. So even after you add more segments, the design gets automatically applied to the new segments!