Hy mandukuk,
at first, welcome to the RWG.
I have a Navitimer rep, too and when it was new, it looks like yours.
The "square look" comes from the paddered strap that going thinner to the deployant.
I think, that is really normal. If you wear it for a longer time, the strap getting softer and rounder.
You have always a problem with the width of the deployant if you have a small wrist.
You can also buy a thinner strap, but I think it looks gruesome in conjunction with the beautiful Navitimer.
enjoy your watch
Friedhelm