Hello Florian,
I do source reconstruction with EEG 64 channels and using fsaverage average brain from FreeSurfer too.
I had the same problem. I was trying to get the trans file using mne coreg but my EEG data did not have the dig points. So what I did is to use the standard 10-20 electrode positions that I read using montage function, when loading the data.
I copied the positions of the EEG channels and the fiducial points into the raw.info[?dig?] structure, saved the new raw file as .fif and then when I loaded it in mne correg I would see the digitized points over the fsaverage brain I previously selected.
Let me know if you don?t know how to do it and I will try to help you but basically you just need to copy the positions into this info structure. Make sure LPA, RPA and nazion are ordered as dig structure requieres, just in case. You can load mne sample data set and check how this raw.info[?dig?] structure has to be.
Hope it helps although if you need more help I can send you my code or try to be more specific. I am not in the office now and I don?t exactly remember how I did it. But it is basically what I am telling you now.
Marina.
El 16/09/2016, a las 09:04, mne_analysis-request at nmr.mgh.harvard.edu escribi?: