I did Samples = 1000 / IC = 50 and it looks ok on the lashes & lips, but you can still see a faint darker shadow on the lower lid from the eyelashes Lower settings just mutes it some.. but then I will add some form of clothing and hair and some other artifact will crop up LOL.

 

 

its quad-core and 64bit. It does render pretty fast. When i first started tinkering with IDL it was like, 4-5 hours per test render. Now if I add hair and clothes and max out the settings its 2 hours.

Render GC - not material.
lash filtering is set to 'quality'.

The lash map doesn't have a gamma network hooked into it. its a straight trans map.