Easy enough to drag an OBJ into my TurboCAD 2016 (TC), use the nimble 3D Booleans to eg 3D Slice apart, re-save as split object...
When it works.
Sadly, when this 'new, improved' OBJ is loaded into Poser, it is often a mess.
Broken faces, artifacts, hair-tear...
D'uh...
I'd got this budget pew+kneeler by francescomilanese from CG Trader
https://www.cgtrader.com/3d-models/...ch-with-kneeler
I needed to slice off parts of a pew to 'book-end' front and back of several rows.
No, the exported OBJs were not 'playing nice'.
They often loaded into Poser like a ST-TOS transporter accident.
And, sometimes, worse...
Yet, the split OBJ file often loaded okay into ($$) 3DOC...
Out of curiosity and, yes, running out of things to try, I re-saved from 3DOC....
Yay !!
Okay, TC had, of course, lost the call to a wood veneer JPG, but that was almost trivial. Fixed in 'Material Room', I was then able to clone the 'intact' pews, the 'seat+back_only', the 'kneeler+stub_front_only'...
FWIW, import pews and parts at ~0.5% original...
The pillars, place-holders for better, in this scene are each a tall Poser primitive cylinder capped / spread by a shorter, wider version...