I face some performance issues regarding activating extended tracking option. Model keeps getting lost in a crazy behaviour. I wonder if there are any more actions to take as i based the app on your sample and only replaced ImageTarget and the augmented model.
Kindly check a video regarding this issue in the following link and a comparison between it and another SDK's extended tracking option under the same circumstances(Model, Image, Lights, etc).
I am using Unity 2018.1.0f1 , and Wikitude SDK V8.0.0 .
With SDK 8 we added optional support for 64bit on Android, which can help with performance. Was this project built with that? You can find more information about how to enable it in our Setup Guide.