My advice as a fellow Mac user .......GET RID OF BRYCE!!! Scrape together $90 USD and get Vue easel

For me bryce "died" around year 2 of the Bill Clinton Presidency

Vue easel will just open your poser .pz3 outright and and save it as a native vue scene

and its preset "atmospheres" and materials make bryce look like the vestgial
anachronistic  tinker toy that it is.
and it renders way faster.

Just my opinion

here is my latest vue render with a poser figure

Good luck 

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