This issue has been closed as 'Won't Fix' due to an extended period of time without updates. If this issue is important to you please let us know by posting on the AnswerHub or UDN, and Epic will re-open the ticket for further review.
A user reported that the Window Position calculation is incorrect with Windows 7 WINVER. The source code appears to be using the calculated left value for the left side of the window, but the calculated right value for the top side of the window.
Head over to the existingAnswerHub thread and let us know what's up.