PSA: Don't fit windows until you've painted!

[bpdlr]

The success rate for salvaging windows is technically 50% at 10 carpentry but it seems far lower (I had 11 failures in a row) so if you're planning on fitting windows, make sure to plaster and paint first! There seems to be a bug where walls can't be plastered/painted, and you have to destroy it and start again - not sure if it's because the window was fitted first, but to be sure, fit the windows last  or else you'll probably fail trying to un-fit them.