Cher Takfa, cher Francois,
Thanks for you replies! See here the file contents:
I can't spot a major difference to yours, but maybe you see something in here. It might be a mac-related problem; I now set up brainstorm on a windows aswell and there it worked fine. I had to manually download the iso2mesh toolbox on my mac, because the automatic installation didn't work properly, but i assume that shouldn't be the issue.
If that's not in your focus right now, don't worry! I know you have a lot on your agenda and I will work on the windows version for now!
Merci beaucoup à vous,
Yvonne