I suspect this is an R3D problem. If I'm working in proxy and I apply the SliceX "blur" I can track it and it works occasionally. However, when I switch back and forth between proxy and R3D, the clip will go green or black and then I be "unfixable" till I replace it with a new copy from the "event browser."
Is this a known bug? Has anyone else had luck using Slice X with R3D's and FCPX?