Created attachment 133501 [details] Original file with two different spacing in LO When you create paragraph with no line spacing in LO DOCX, then open it with MSO line spacing is not same as LO. However Sapcing:1 Single have no isse.
Created attachment 133502 [details] Same file after it is opened in MSO 2016
Created attachment 134078 [details] printscreen of the style settings Can you reproduce it with new file? I see the the problem in your file, but cannot reproduce from scratch. I made a copy of your style "Normal(web)" and when apply the style, the spacing is present. In the style is spacing set above a below paragraph.
I have found workaround to resolve spacing issue. I select "clear formatting" from styles then I select spacing again and now it is fine in MSO.
Created attachment 134094 [details] MSO file after clear formatting the add spacing again