Constrains and laminates

Hello, id like to simulate a laminate with around 5 isotropic laminated layers. These layers are in the form of a plate with a constant area load. The model is a laminate for photovoltaics with area load of snow.

First of all, id like to set up specific boundaries of areas. As i know from using UGS NX5, i want to define reference areas on the 3D-Plates at wich i want to set up my boundaries from the botton side and at wich i want to integrate my circular area loads from top side.
I didnt find a function yet for creating reference geometry wich doesnt affect meshing. Is there a way for it?

Also i want to create a 2D Beam of this laminate and directly integrate a specific lineload at a defined line on the top surface. While doing a test with a pressure load coming from the top and fixed points at the edge i just got the error that my error is bigger than my tolerance. what am i doing wrong? I also thought about creating an infinite beam with defined lineload. The result should show the influence pressure of a stamp on this laminate so im just interested about the distribution of stress.

Thanks for your reply, maybe you can clear my problems ;)