Hello,
The positions of the electrodes are not saved in the format Brainstorm expects.
Can you send me an example .set file for which you have this issue? Upload it somewhere and send me the link.
Maybe I’ll find a solution for reading information from this file in a better way.
Otherwise, you can edit the sensor positions manually: right-click on the channel file > MRI registration > Edit. With a combination of resize/translation/rotation operations, I managed something decent.
If these are standard electrode positions (as opposed to digitized on the head of the subject with a Polhemus), you can probably find and equilvalent set of positions for your cap in Brainstorm (right-click on the channel file > Add EEG positions > ICBM152 > …)
Cheers,
Francois