Problem 1 - right-click on the exe and select Run as Administrator.  Then Poser should install fine on Windows 7.  Anything that uses the Program Files folder needs to be run this way.

Problem 2 - just download again from your account.  You can switch what type download (Mac/PC).

Problem 3 - no idea.  In theory it should work, but you need to configure Vue to see the Poser folder. 

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