I have two technical problems regarding the installation of the captioned crankset.

Firstly, I note that the seal of the drive side bb cup is of a piece of metal in concave shape with rubber external. It's difficult from the seal of the non-drive side bb cup, which is flat. Is it normal? Secondly, I installed the whole set of the crank (left and right) and reached the recommended torque. I notice that the non-drive crank arm touches the seal of the bb cup completely (full contact). Itís seems ok. However, there is a gap (2-3mm) between the seal of the drive side bb cup and the crank arm. (I do not notice any play in the crankset.) Is it normal? Is the concave shaped seal of the drive side bb cup purposely made to preload the bearing?

Thank You for your kind attention.