runtime compilation of shaders is no longer supported

[tony56a]

Pretty sure you're not checking this, but just in case, CS just updated their Unity version to 5.4, which includes the following change:

"Graphics: Deprecated Material(String) constructor further. This will now always create a material with the error shader and print an error, in both Editor and player. It will be completely removed in a future Unity version."

This is causing the pathway arrows to all look purple.

The fix for this is to compile the shader aot, and load it via assetbundles or something.