Hello Francois,
I was able to create a list of electrodeposition in 3D Slicer and save it as cvs file. I edited the file and kept only the XYZ position and the electrode name. I did include LPA,RPA, NAS. In Brainstorm, I opened the file as ASCII XYZ,name. The position of the electrodes was way off the head and the three points(LPA,RPA, NAS) were not part of the electrode list. How do I align the imported LPA,RPA, NAS with the head model points and how do I do the coordination transformation you mentioned in your reply. Again, I really appreciate your help, I am a medical doctor and not familiar with these concepts but trying to learn.
Waleed