ErickL88, as others have said, inverse square falloff is the most physically accurate model, so it's highly advisable regardless of other settings.

Asuyuka, off the cuff, it sounds like you may be using the wrong channel, but we do need more detailed info to tell for sure.

Anyway, here's another render for which I used VSS to apply my shaders, this time to M4.  This was also a bit of an experiment, since I have light-based AO enabled for the benefit of the Stonemason set I used for the surrounding scene (even with VSS, adding matterial-based AO to every piece of a Stonemason product would be a colossally tedious exercise, one that I wished to avoid if at all possible).  However, there's still material-based AO on the character and his clothing.  The theory was that since I have the "Evaluate in IDL" checkbox unchecked and IDL enabled, the AO node should do little if anything beyond signaling that I do want some AO on the figure (I've determined that it does that because removing it in IDL renders mysteriously resulted in renders with that characteristic flatness of AO-less scenes).  Hence, the unrealistic doubling-up of AO which you might expect with both light-based and material-based AO enabled should not occur.  I was skeptical, but my risk seems to have paid off!

In any case, given that VSS is a tool suitable for a "King," I thought the subject particularly appropriate, LOL!

Rendered in PoserPro 2010 using inverse square falloff on a single, infinite light.