The lever on my 1620 sits just about centered when closed. I’m not sure how the left/right of center thing applies to these Greener cross-bolt guns. Perhaps someone else can chime in.

I bought my gun new and it was really tight out of the box. The factory said this is normal and I’ve heard many others say this about their Merkels. It took many, many rounds to get to the point where the cross-bolt would seat on its own without having to nudge the lever a bit.