I got the exact problem.
I interchanged the HDMI for my monitor and PIMAX and got it working but after 2 reboots it is same and this time the previous solution(interchanging HDMI ports) doesn't work either.
I noticed that windows has detected another display and i can move my mouse on it without actually seeing the cursor.
Tried to delete the display by going to multiple displays in control panel but no luck.
For me the above solution works sometimes but it is more like trial and error.
But i can assure you that changing to different PIPLAY versions is absolutely not the solution.
I will contact their email for this.