To reproduce:
1. Open an empty project in Unity4
2. Import the package the user attached into the project (remove the .unsafe extension from the filename)
3. Open the scene "Scene"
4. Open the object "Car" in the hierarchy
5. Open the object "All" inside "Car"
6. Open the object "Vehicle Animation" inside "All"
7. Open the animation window
8. Open the animation "VehicleTwistRight"
9. Notice that transform.scale.z is always 1.
10. Open a new project in Unity 5
11. Repeat steps 2-8
12. Notice that transform.scale.z is always 0.

Regression since Unity 5