On a new layer I did the same Polygon Lasso effect for the darker areas, using #2A579C. Then applied a 'Filter/Blur/Gaussian Blur of 1.1 pixels' and reduced the 'Opacity' of the layer to 30%.
Next I'll add the windows.
For this all we have to do is reuse our original 'Shape 2' for the backgorund windows, and the 'Shape 2 copy' for the forground windows.
First duplicate the original 'Shape 2' layer and call it 'backgroundwindows'.
Once its duplicated drag it below the orignial 'Shape 2' layer in the 'Layers Palette', as I have captured.
Then hit the 'A' key to select the 'Direct Select Tool' from the 'Toolbar', then hold the 'Shift' key and select the background windows individually.
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