For Question 1

Andrei, who is/was a big MoI user, preferred Nvil out of all the polygon modellers out there.

The default Nvil interface is not so good but he has created a simpler interface which has been workflow refined and you can download the exe file to install it. http://nvil.info/about

He also created a bridge tool between Nvil and Moi although right at the moment that website is down or he has removed it.

Very nice modelling job on the weapon. Just needs lots of uving, textures and some nice renders to bring it to life.