Steps to reproduce:

1. Open the attached project 'RenderOnce'
2. Open 'test' scene
3. Script is attached to the cube which renders disabled camera in the scene ( Camera.Render() )
(According to the documentation: "This is used for taking precise control of render order. To make use of this feature, create a camera and disable it. Then call Render on it."
4. Play the scene
5. Press space
6. Nothing happens
7. Build on standalone
8. Press space
9. Now cube becomes visible in the scene