Metal Slug XX

[thatcadguy]

It's my general understanding that to get the netplay to work with any 2 devices on the same network:
1) you enter in the IP of the device to be server
2) enable networking/WLAN
3) one device needs to have the enable server checked
4) devices need to have different MAC addresses

I've gotten this to work on Metal Slug XX using a PC as the server between PC/Android. But on the same game, trying to use Android with Android, or Android being the server results in connection error when trying to start the game. The games will start and you can select network game and see the other device, but when you actually go to start playing it says connection error. It's also my understanding that Metal Slug XX is a supported/working game.

Is there an extra setting I forgot, or a known issue with PPSSPP on Android being the server? Does PPSSPP need to be root on Android to open up the correct ports as the server? TIA