Just now I set up a scene with the exact same contents, two alysons with the ultimate texture, the studio backlight as well, started the render (separate process on Windows XP64 with 2Gb) & it froze at exactly the same spot with both processor cores maxed out.

Cancelled that & restarted Poser, set up the same scene with 2 Alysons & left the textures as the standard one they load with & it rendered to the end in under a minute.

So I tried a single Alyson with the ultimate texture closeup (so I can see exactly where it stops) & it's freezing as soon as it starts on the Iris, I took out the extra math node in both Iris & it renders to the end this time.

Perhaps someone with intimate knowledge of maths nodes (bagginsbill) can explain why a single node will bring the render to a standstill cause I'm stumped.

Windows 7 64Bit
Poser Pro 2010 SR1