I'll email you the 4.0.217 dev build that updates so desktop pre-warps with WIn 8.1. Bear in mind that there are still several issues with 4.0.217 but it should work with desktop and P3D 2.4 on AMD.
Thanks, it'll be helpful. So far only 3 users have access to the 4.0.217 build. Getting feedback and data on it will ensure any bug that might show up don't make it to the full release version.