I've started with the beveling.
All successful but i have a problem when beveling the windows:



Here are close-ups before smoothing and after smoothing the beveled windows:

Before


After


I have no idea why this happens, all i've done was adding a bevel to the windows.
I've tried to the use the Cleanup tool to split faces that are 5 vertices, i've tried merging vertices (in case there are any discconections), still no luck though.

any ideas? :headbang: