Problem with mesh

As you have still not supplied me with a mesh, I cannot do much to help you.
What I am linking you to in the previous post is that the xml file most likely contains the domain markers, and you can extract them from it.

If you want to make something that works in parallel, you need to do the following:

  1. Use the meshio python interface to convert your mesh from your .mesh format to XDMF, as described in: Transitioning from mesh.xml to mesh.xdmf, from dolfin-convert to meshio - #174 by dokken, where the cell_data variable is replaced with the array you are describing (one integer per cell).
  2. Read in meshvalue collections and place then in a MeshFunction, as described in: Need help converting GMSH to FEniCS - #17 by dokken