Windchill Desktop Integration is not required to manage Microsoft Project Project Plans with Windchill. The editing and exchange of Microsoft Project with Windchill Plans is controlled by the PTC Plugin for Microsoft Project. The download is located in the same place as DTI: Quick Links, Software Downloads, Project Management.
Details on how it works is located in the Windchill HelpCenter under Microsoft Project Integration.
The Windchill 10.2 Software Matrices only lists support for Microsoft Project 2007 and 2010 at this time.