Dear @Borek_Patzak,
on my side I didn’t have an error when I load your data at step2, which version of vtk do you use? I try it in ParaView Master.
Regarding your example, everything is fine unless the Part and NumberOfParts which are not handled correctly.
To be honest the documentation regarding Part isn’t clear for me too, I will see how I can improve the documentation regarding your use case.
In the meantime, could you please try this corrected version of your data?
se2.out.m0.hdf (107.7 KB)
Here is what I have in paraview:
is it correct?
Best