I found that the "Render" and "Stop" button in Corona Rendering setting panel and VFB, is not work sometimes. when I stop the rendering, the stop button in VFB is still there.
And another one is when I hit the render in Corona Rendering setting panel, The VFB didn't show the rendering process. In Corona Rendering setting panel it shows pass 9 maybe, the in the VFB, the image popped up suddenly.