This is why we like to have all the answers posted on this site instead of having them e-mailed to you directly!
Meaning no disrespect to Marina but,
I would contact the window manufacturer to see if the windows were installed properly.
I do not believe there should be any movement in the mulls of the windows.
By adding foam insulation you could do more damage to the windows than good because the foam could expand to the point of cracking the glass.
It could also void any warranty you may have.
If you had the windows installed, tell your contractor that you would like to see the factory rep.
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