From this error report, it's difficult to know whether the problem is coming from a bug in Brainstorm, a bug in OpenMEEG, or a manipulation error on your end.
Could you please try to assemble a small dataset for us to reproduce your error?
- Create BEM surfaces with a low number of vertices (eg. 272).
- If you are using a volume head model, use a grid of 15mm (~ 100 points)
- Run the computation from Brainstorm, and immediately after you get the error message, zip the the contents of the folder $HOME/.brainstorm/tmp, upload it somewhere and post the download link here.
- Include a screen capture showing the anatomy of your subject in the database explorer, and another one that shows the channel file.
Thanks