While working on my Mayflower, I came across some material that makes excellent diamond pane windows. Photo-etched brass mesh, from K&S Engineering, in their "Special Shapes" line(www.ksmetals.com). Its a flat sheet of fine brass mesh that cuts easily and can be chemically blackened if desired. I found it at a local hobby shop.
I cut out sections just a little larger than the window its for, blackened them, then painted them with grey, glued them to the interior of the hull, and followed up with clear plastic sheet for the "glass."
The mesh is so fine you have to look to see it, and it has a flat surface, rather than a weave like wire screen. I used the 1/8 diamond, stock No. 02712 for the 1:70 Mayflower and it came out beautifully. Smaller sizes are also available for smaller scale ships and projects.
The neat part is seeing light reflect off the windows, even the small ones on the hull sides, giving depth to the build.
Jim