reading physical groups gmsh mesh file in NGSolve (mpi build)

Dear NGSolve developers;

I’m trying to read a mesh file generated using GMSh, the geo file reads:

Mesh.CharacteristicLengthExtendFromBoundary = 0;
Mesh.CharacteristicLengthFromPoints = 0;
Mesh.CharacteristicLengthFromCurvature = 0;
//+
Mesh.CharacteristicLengthMax = helem;
Merge "Geom.STEP";
Physical Surface("plane6_geomA") = {6};
//+
Physical Surface("plane8_geomB") = {8};
//+
Physical Surface("plane7_geomC") = {7};
//+
Point(90001) = {0, -43.150, 0, 1.0};
//+
Physical Surface("other_geom_srf") = {4, 9, 14, 1, 10, 3, 11, 2, 15, 17, 16, 5, 12, 13};
//+
Merge "sphere.geo";
//+
Surface Loop(30002) = {13, 1, 5, 11, 2, 8, 10, 3, 7, 9, 4, 6, 12};
//+
Surface Loop(30003) = {16, 14, 15, 17};
//+
Volume(40002) = {30001, 30002, 30003};
//+
Physical Surface("sphere_srf") += {20025, 20019, 20023, 20021, 20027, 20029, 20015, 20017};
//+
Physical Volume("air") = {40002};

While the mesh generated with the above geo file using:

subprocess.call(["gmsh", "-v", "0", "-3", "-setnumber", "helem", str(helem), "-setnumber", "R1", str(radcomp), str(basegeofilename), "-o", str(meshfilename)])

and then reading it using:

if (rank==0): mesh = ReadGmsh(meshfilename) if (nproc > 1): mesh.Distribute(comm) else: mesh = netgen.meshing.Mesh.Receive(comm)

The mesh file read goes through in the NGSolve installed on my linux PC (NGSolve-6.2.1909). However, the same piece of code and mesh fails to read when i use NGSolve on cluster (mpi build). Since I am using GMsh to define my physical surfaces as well as volumes, i am not sure if i need to do anything additional to define the face descriptors as mentioned in another post here.
What do you think could be the source of the problem? Thank you!

ps. I hope everyone is keeping safe amidst the current outbreak of covid19.

I have never worked with gmesh before and I am not sure wether it should work with MPI or not. Could you send me a complete example file, then I can maybe figure out if the problem is something simple or something major.

Best,
Lukas