I have the same issue, except the VR controllers disappear entirely when I test my project, both in the preview and when I export it as a standalone game. When I rolled back to any of the previous versions, the controllers appeared as normal, but the spectator mode had a resolution that was larger than my monitor (the latter issue was solved by updating the engine). I think this has to do with how the old motion controller input variables were deprecated for individual variables based on different headsets, though the Vive inputs generate errors saying that they are not blueprint bindable.TDespite this, the controllers show up in the steam VR home and in other applications except for the one that I am making. I am very new to using Unreal, so I am not sure if my logic is correct.