How to create Montage in ECoG data of Nihon Koden and information about "lh.seghead"

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MNE version: 0.24.1

operating system: Windows 10

Platform: Windows-10-10.0.19043-SP0

Python: 3.9.9 | packaged by conda-forge | (main, Dec 20 2021, 02:36:06) [MSC v.1929 64 bit (AMD64)].

Executable: C:\anaconda3\envs\mne\python.exe

CPU: Intel64 Family 6 Model 151 Stepping 2, GenuineIntel: 24 cores

Memory: 31.7 GB

mne: 0.24.1

numpy: 1.22.0 {blas=NO_ATLAS_INFO, lapack=lapack}

scipy: 1.7.3

matplotlib: 3.5.1 {backend=QtAgg}

sklearn: 1.0.2

numba: 0.53.1

nibabel: 3.2.1

nilearn: 0.8.1

dipy: 1.4.1

cupy: Not found

pandas: 1.3.5

mayavi: 4.7.2

pyvista: 0.33.2 {OpenGL 4.5.0 NVIDIA 512.15 via NVIDIA GeForce RTX 3090/PCIe/SSE2}

pyvistaqt: 0.7.0

ipyvtklink: Not found

vtk: 9.0.3

PyQt5: 5.12.3

ipympl: Not found

mne_qt_browser: 0.1.7

pooch: v1.5.2

I am working on a tutorial on ā€œLocating intracranial electrode contactsā€ and have two problems. The first is the creation of the lh.seghead file required for Head->MRI conversion, and the second is the creation of the Montage file used for positioning to the standard brain.

The MNE sample has a file called lh.seghead (in MNE-misc-data\seeg\sample_seeg\surf), but it is not in the data generated by Freesurferā€™s recon-all.

I know from the notes that it is possible to create them by using mne.bem.make_scalp_surfaces, but I donā€™t know how to use it.

I donā€™t know how to use it (I canā€™t find any reference to it), so I canā€™t create it.

RuntimeWarning: seghead not found, skipping head plot, see :ref:mne.bem.make_scalp_surfaces to add the head

gui = mne.gui.locate_ieeg(raw_ecog.info, subj_trans_ecog, CT_aligned_ecog,

I think the second is related to the first.
The calculation and definition of the Matrix to be converted to Head->MRI is done in the first calculation.
You need to use that Matrix(subj_trans_ecog) when aligning to the standard brain.
subj_trans_ecog = mne.coreg.estimate_head_mri_t(ā€˜sample_ecogā€™, op.join(misc_path, ā€˜ecogā€™))
I skipped it for now, since the first one was just noted, but
I canā€™t confirm what effect this way would have on the next analysis.
If I position it to the standard brain as is, I get the following error.

-ā†’montage.apply_trans(subj_trans_ecog) Problem line
AttributeError: ā€˜NoneTypeā€™ object has no attribute ā€˜apply_transā€™

Since the problem with Montage is also in the coordinate system conversion between Head and MRI, we think that the creation of the first lh.seghead file is important.

(1) Function, impact and creation method of lh.seghead
(2) How to create Montage in ECoG data of Nihon Koden (currently using mne.channels.make_dig_montage())

I would appreciate any information on the above two points.