The head surface is generated by Brainstorm, not by CAT12.
First, check that the outputs of CAT12 are correct: Open the cortex surface and the volume atlases to make sure the segmentation worked correctly.
Then try to recompute a different head surface from the MRI, following the instructions on that page:
https://neuroimage.usc.edu/brainstorm/Tutorials/LabelFreeSurfer#The_head_surface_looks_bad