Citra black screen/sometimes grey help

I have an issue with Citra emulator, trying to run Pokemon Ultra Moon on my Nvidia shield.
Game starts fine, then certain graphics of the game is black with sound, sometimes grey.
E.g I can move, walk fine etc, I can interact with other characters fine, text is displayed fine in the speech bubble, but I cannot see the world environment or my character???
Tried following the Diagnostic chart tutorial below, but there is no explanation for Android/Nvidia Shield.
Any help is greatly appreciated.

System Information

Diagnostic Log
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In order for us to provide better support, we need to see the log generated by Citra. This guide will walk you through how you can obtain the log file: How to Upload the Log File.

The official version for Android has not been released yet, we do not provide support for unofficial builds.

Thank you, I was unaware of that.