No issues with Poser Pro 2012 and Windows 8 here.  I have not upgraded to 8.1.  As a desktop user that doesn't give a single care about the Apps, Start Screen or the Charms Bar, I don't see any need to move up to something that is less compatible with what I use.

I read quite a bit on 8.1 and see no effort to enhance the desktop environment.

The only reason I even use Win 8 is that I had a HD meltdown last year and decided to do a full upgrade of my system.  Win 8 Pro was offered at a steal so I took a chance on it.  Once I swept away all the stuff that I mentioned above, it works much like Windows 7 here and I'm fine with it.

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