In practical terms, this means that the surface I select as cortex should be contained within the source grid I define when setting up the head model computation, right? If this is the case, in principle DUNEuro should not fail if I select the gray surface as cortex, force the source space to gray and generate the grid within the whole head, am I right?
To clarify: I am working with EEG, not sEEG. The sensors are on the scalp.