Re: Only some curtains display in some windows
I took a look at this in both my main save where I play with mods and CC and in a vanilla test game with no mods or CC. I don't use CC windows, but I do use a bunch of CC curtains. In both saves, I had no problems seeing the curtains. game or CC, through the windows in either build or live mode. So, I could not replicate what you have happening.
But I don't have the windows or blinds I see in your pics. My gut feeling is that the issue is CC related. So, it could be either the CC windows or the CC curtains/blinds or a combination of the two causing it to happen. It could be that one or the other is causing a clipping issue preventing both from being seen. It could also be MOO related if you used MOO to place either the windows or curtains as well. The curtains you mentioned not showing next to the stairs could very well be MOO related as to get many curtains to place next to stairs or in stairwells, you have to use MOO. But, tbh, I just don't know.
Have you tried to replicate the problem in a vanilla save with no CC or mods present? If it doesn't happen in a mod/CC save, then that's a sign that it is CC related.
Hope this helps.