Thanks everyone.
Jipe: A lot of trial and error.
One thing that helped majorly was a Yafray GUI I downloaded called
Bagisas. It is set up exactly like the entity menu is in Radiant. It also has quick and dirty render previews right there on the GUI, and it has drop-down menus for all the different light settings, which is really helpful.
One thing I did that really helped get me started was downloading a pre-made XML file which set up the scene nicely, then adapted it to my own needs. There are 3 lights at play in the render; a sunlight (the yellow), a pointlight (provides most of the shading), and a hemilight (kind of like ambient light.. this is what gave it a somewhat grainy appearance and lightened it up considerably). The XMLs I downloaded to set up the scene can be found
here.
Also,
this was a very helpful read, about rendering lighting.
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Have a good one,
Freelancer