进行安装提示先安装UE4 4.16,但是我已经安装了UE4 4.19，是否需要再安装一个4.16版本？

Yes, You have to install UE4.16.3 for PiStage 1.1 trail.

Install UE4 4.16 first, but I have installed UE4 4.19. Do you need to install another 4.16 version?