As for the windows, here are some steps I generally put a Gothic window quickly together. Without any further explanation - so if you have questions, refer to the image numbers... Just one note; at the end of the "tutorial", we end up with a window (see also attached) whose outer part is there but if you want to get it to cut both faces of a thick wall, some further steps are needed.
Edit: some of the png files are so small (in file size) that this stupid forum software does not even create thumbnails. Please, click on the attachment links.
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