It can be lots of work !!
I usually put a similar write-up on DA linked to/from original, so next would-be
Poser importer has the recipe.
IMHO, FBX importing is unlikely to improve 'for some time' as official comments on Rendo' suggest they first have to build a 'bullet-proof' Unimesh rigging system which stays compatible with existing system.
Comment iteratively edited by duty-cat, between sitting in front of, or patting current screen, chasing cursor and complaining that some-one's turned off the Summer again. Thankfully, she's now retreated to desk's RH pull-out for a well-earned sulk...