Sketch up Model viewer problem

App is running pretty strong on new iPad Pro. Only problem so far is some faces appearing as if they are facing the wrong way. they are not. It appears to be related to mirrored objects but not sure.

So if I go back and copy not mirror objects they display correctly so problem is related to mirrored objects. Also processed PC model through 3D Warehouse instead of from iPad.

Now going to check if the native sketch up mirror function and the mirror plugin both produce the same error.

Shadows would be nice but I understand hardware overhead could be to high.