the vendor of OP's product may have specified some settings due to small details like the eyelashes, for which OP didn't supply a screenshot to allow checking the imagemap node settings.  the eyelashes would probly look spotty and clumpy with default settings.  the shading rate is a value that allows an estimate of the relative number of calculations per screen pixel.  if all the other settings are such that FFRender is doing n calcs per screen pixel at shade rate = 1, then FFRender is doing 5n calcs per screen pixel at default posersurface shade rate = 0.2.