UE4 Stuck after Selected Camera in Level

Recently, I worked on a project with engine compiled from NVIDIA Waveworks branch. (The branch name is waveworks-4.16 in github.) All the functions relevant to Waveworks are good to work. But once I put a camera into current level, UE Editor will get stuck and close with error several minutes later.

I also did some test, and found that only when I selected the camera and the preview window appeared at lower right corner, the UE Editor stuck. Seems that it can’t render with two cameras (main view and the camera preview), because I had received a error about “D3D device is lost” one time.

So, does anybody have some idea about this situation? Or is there some settings need to change? Thanks a lot.