This is probably already out there, but I’ve got Beta 1.5 and neither the apostrophes or quotation marks show up if they are ‘smart quotes’ when I copy and paste.
I did poke around the forums some, and there are some things there, but they were all for Beta 1.4 and so I figured that I would comment that it still happening in beta 1.5. 
Hi,
Please note the following links.
They are about Beta 1.5
[url]https://forum.literatureandlatte.com/t/apostrophes-replace-by-quotation-marks/10527/1]
[url]https://forum.literatureandlatte.com/t/beta-1-5-import-accents-not-completely-solved/10451/1]
[url]https://forum.literatureandlatte.com/t/copy-from-word-file-loses-all-apostrophes-quotes-fine/10490/1]
And they are all about the same topic.
And of course here: https://forum.literatureandlatte.com/t/apostrophes-disappear-when-importing-rtf-bug-logged/10225/1
Although it’s about 1.4, it deals with the same issue and has some workarounds.