Dear Joan Paul,
I’m sorry, there was no update on this topic since the last time you asked on the forum…
As part of Brainstorm, we only have a 7-week atlas from Ghislaine Dehaene’s lab:
http://neuroimage.usc.edu/brainstorm/News#October_2014
Similar posts on the forum suggest some other ideas:
http://neuroimage.usc.edu/forums/showthread.php?1976-Compatible-with-bst-template-format
http://neuroimage.usc.edu/forums/showthread.php?1711-MRI-template-for-children
You could try to contact other labs that are doing source reconstruction on children MEG/EEG recordings. Maybe some of them already have this figured out.
If you find good models that are freely redistributable, we could include them in the Brainstorm distribution like we did for the 7w template.
Cheers,
Francois