[kontra]

I am looking for a preprocess tool (CAD) and a mesh tool
licensed under LGPL (Lesser GNU), BSD or compatible license.

The crucial feature for me is the capability to assign boundary conditions on selected surfaces so I would be able then to use the mesh as input to a solver.

I tried FreeCAD but doesn't offer assigning boundary conditions feature.
Gmsh does offer such capability through its geometry module but is licensed under GNU.
Salome seems to include this feature but it's so complicated to use.

Any other suggestions?

In short, can you suggest me a flow of tools, under LGPL/BSD-like license, I can use to prepare the input for a solver?

[cdegroot]

Sounds to me think something you are going to have to pay for, especially if you want it to be easy to use