a. YA(G)Max export simple omni (no attenuation/decay) as sunlight. Which light from infinite through the position of the omni to the center of the scene. If there are something between the light path, The light blocked.

b. YAFRay render every object/geometry as double-sided. 'Flip normal for see through' type didn't work with yafray.

Why my rendered image so dark? Even I added few more lights didn't help!

YAFRay's light(except sunlight) are base on real world physic. So light intensity decay over distance(Invert square law).
For example: Place a 1 unit sphere located at [0,0,1], a pointlight located at [0,0,3], multiplier equal to 1

now move the pointlight to [0,0,7]. Increase the multiplier to 25

Move the light to [0,0,12]. Multiplier to 100

They all have same intensity!

How can I disable shadows in YAGMax!

YAFRay lights: sunlight, pointlight and spotlight support 'no shadows'. However GMax seems to have bugs on cast shadows checkbox control! So what you can do are:
a. Select the light you want do disable shadows. In Maxscript Listener type '$.castshadows = false'

b. Use YA(G)Max's Lights Lister to control all general lights properities.

There is no such problem with Max!

Kam � 2005.