Sry I didn’t see the line “I set up my geometry using CSG”.
You can do the same thing using a meshsize file as described in this documentation:
See 4.1 mesh size file.
I think all of the functionality of the CSG interface is now exported to Python as well. The syntax changed slightly, but internally the same C++ code is executed. It got more powerful, because you can use the full potential of Python.
The old geo files will be supported in the foreseeable future as well, but wont be further developed any more.
Basically your code in python would look like:
from netgen.csg import *
geo = CSGeometry()
sec_0 = Plane(Pnt(0, 5, 0), Vec(0, 1, 0)) * Plane(Pnt(0, 0, 0), Vec(0, -1, 0)) * Plane(Pnt(0, 0, 0), Vec(-1, 0, 0)) * Plane(Pnt(1.5, 0, 0), Vec(1, 0, 0)) * Plane(Pnt(0, 0, 0), Vec(0, 0, -1)) * Plane(Pnt(0, 0, 50), Vec(0, 0, 1))
geo.Add(sec_0)
The user meeting will mainly focus on NGSolve not Netgen. So if you are only interested in Netgen I would not recommend it. If you want to learn how to do FEM in NGSolve we will be happy to meet you in Portland 
If you have need for (professional) Netgen support you can contact me at clackner@cerbsim.com. We started a university spin off this summer to support companies in using Netgen/NGSolve.
Best
Christopher