MentalRay where to start?

I hope I picked the right forum?!

I new to mentalray-rendering and all ready tried a few shaders and lighting setups. But as it comes to the point of adding more stuff to a scene, I get pretty fast lost in weird renderings.
This is no request for tutorials, I liked to know how you got into MR?
What is the experience? Where to start?

I'm interested in learning lighting and creating materials for in- and outdoor scenes.

edit: (oh forgot to mention I'm working with 3dsmax)

It is impossible to explain the whole mental ray in one message.
What you can do when you start having weird stuff is remove everything from the scene and start rendering one by one. This way you will see where the problem is. When you find the location you can then start playing with parameters the same way. This way you will learn a lot of stuff that can be learned only through experience.

Thanks for your input.
Trial and error seems to be my friend all the way.

Just the realtime-support is missing here.

What do you mean by realtime-support? The support of realtime shaders?

Yes, active view helps but well... it's still rendering, tweaking, rendering, tweaking...

I'm just having hardtime finding the correct setup. One material looks good and the other got artefacts.

I don't know about 3ds max but in softimage xsi there is support for real time shaders but they are for real time applications only and not a part of mental ray in the sense that the real time shaders are not renderable.

Anyway tweaking, rendering, tweaking is the best way to learn