Here is something interesting... (stupid google)... I tried to do another search, instead of "Poser wont load libraries" or some version of that, I accidentally typed Poser 8 (I forget it is 8, its 2010 to me)... One choice that came up was "Poser 8 blank library"... Which led to this from SM: https://support.smithmicro.com/app/answers/detail/a_id/2211/~/poser-8-blank-library 

I cant get their method to work... but its not a surprise since it only covers Internet Explorer and not Safari.

I hope this method works for you... but it shows there is some connection to something internet related.