Sorry, didnt se the part were he asked for ambiant occlusion and subsurface scattering.

I did however see the part "I'm pretty much an amateur here" and figured that Batsarse could use some hints on how to use his current software.

Talking about Atari 800 graphics seems a bit out of context here, can you show a comparision between that and the output of the P4 render engine?  :-)

Regards / Jonny