Just a few quick notes:
-You can find the 'actual' AO shader in the example project, it should produce the same results as the one in the tutorial.
-Distance control isn't implemented because it wouldn't improve the shader's performance in RS (might be different for V5).
- Reflection occlusion is really simple to do, just change the raytracer's direction param to Reflected Ray.
-Bent normals aren't hard to implement, but I don't think they'd be that useful.
-Spread and samples act pretty much the same way as in the tutorial.
-Brightness mapping isn't hard to do, but you might as well use one bounce GI with envMap.
When it is darkest, men see the stars.