Couple of things to note:
1) 8.2 DLLs may conflict with current solution's MVC. If that is the case, then you will need to add the following:
<dependentAssembly> <assemblyIdentity name="System.Web.Mvc" publicKeyToken="31bf3856ad364e35" xmlns="urn:schemas-microsoft-com:asm.v1" /> <bindingRedirect oldVersion="220.127.116.11-18.104.22.168" newVersion="22.214.171.124" xmlns="urn:schemas-microsoft-com:asm.v1" /> </dependentAssembly>
2) With Sitecore 8.1 Update 3, the location of the Social renderings moved from /layouts/system/Social to /layouts/Social. This means that you will need the Social renderings in the new location in order for the authorization return to work as expected.
I've uploaded the files I used to resolve this. As always backup current solution before deploying in case you need to roll back. Enjoy the patch!