You pipeline looks good.
Here I believe the initial problem started, if the FEM mesh calculation gives the popup "Overwrite data in the anatomy folder"
I fixed these problems with the two commits below:
- Bugfix: FEM mesh with SimNIBS: Do not delete the anatomy · brainstorm-tools/brainstorm3@1c25f84 · GitHub
- Bugfix: SimNIBS import: Missing returned values · brainstorm-tools/brainstorm3@76e4345 · GitHub
Please update Brainstorm before you try running SimNIBS again. Now it should not erase the existing anatomy files anymore - just add more files (be careful with selection of the default cortex after that...)
For each EEG datafile then I calculate the sources ("Compute Sources 2018", with the choice of Minimum Norm and Current Density Maps, given my goal)
If the different EEG files are imported in different folders: yes.
If they are in the same folder, you only need to compute one shared imaging kernel for all of them.