The issue with the Medium vs Full trust is resolved as of this morning. The problem was actually that the latest .net framework changed some of the basic Security principles. I've adjusted the core build to support the change. However - when you switch between Full and Medium trust now, you will be limiting the availability of some of the core actions. For example, under Medium Trust the File Action will not be able to access the standard File IO library as it did before. I need to toy with it more to see the exact cause of the limitation, but it shouldnt affect anyone running under Full Trust. Additionally, the issue with OWS.Fetch which was causing problems in the JS Framework as well as Posting Files has been resolved. I'm continuing to test out the rest of the Burn in tests to see what else has broken.