I use Windows 7 64bit and I also cannot use my saitek fip in p3d v2.3 either. I didn't find the exe.xml file in p3d only a dll. Have you made any progress in the situation?
I have six of the Saitek FIPs and cannot get them to work with P3D V2.3. If I don't have the exe.xml files from FSX to copy/paste then what do I do? I downloaded the direct output file from Saitek but it doesn't appear to install into P3D.