Hi Tim,
Sadly no joy I’ve uploaded two APK’s incase you wanted to see it on the Ouya, I could also share the project files if that would help?
Epic’s build with no Ouya support AI WORKS
https://drive.google.com/file/d/0B4o9SD56_m3IU0M5RGI4bGQ1UnM/view?usp=sharing
Ouya build
https://drive.google.com/file/d/0B4o9SD56_m3IRnJZSEFHRUtRWFE/view?usp=sharing
Stuff I’ve tried
a) Copying DefaultEngine.ini from the project that works to the Ouya build no difference.
b) Compared difference Version difference,
Ouya UE4 = 4.7.1-0+++depot+UE4-Releases+4.7
Working UE4 = 4.7.1-2462028+++depot+UE4-Releases+4.7
c) I’ve logged the blueprint with prints on the Ouya version just to check it goes through the nodes (gets stuck on AI MOVE to).
d) To ensure it’s not something to do AI MOVE to I went and set up a really simple behaviour tree using this article (works fine on windows)
e) Another issue, the games stopped appearing on the play menu, I think the lines there in the manifest for it.
Knowing me it’s got to be a tick box, but as the issue seems to have gone from 4.6 → 4.7.1 in the Ouya branch I have no idea where or what it is 
Sorry it’s not better news. I’ll keep thinking but any ideas?
All the best
Greg