the thing to keep in mind with maxwell is that basically you are on your own... it's the whole "beta" thing I'm thinking.
Some of the documentation that comes with it helped me a lot. Make sure you read the manual and fully understand what EVERY component in the Maxwell panel does. It's a mistake to discard something because it doesn't make sense or doesn't seem relative to what you want to do. Most of everything in Maxwell affects everything else in Maxwell.
Next. (tackle things in chunks)
You need to figure out how your software (lightwave, Max, etc) deals with maxwell's rendering engine. In lightwave there are only a few specific texture and numerical inputs that are active... Knowing which ones and how they affect the final render is critical.
For example, without careful prep, or reading the manual, you wouldn't know not to load glass, lights and objects in with the same object... like I ordinarily did with Lightwave. I spent a bit of frustrating time figuring out why my emitters were... well... non-emittive. and why my glass was a pain in the a%%.
Then there is doing all the tricks we are used to. UV texture mapping. radiosity texture based lights, HDRI stuff... all that. How does one texture something with both bump and specular...?
Read the forums. Attack things in a 1,2,3 manner. understand each component before moving to the next. To create a truly realistic image one must understand how maxwell gets to that point, so we can mess with it in the process.
it's worth doing, good luck.