Honey_ZA - I've been away for a while so haven't caught up with everything that's been happening with IDL, but there are a few things that I do know might be worth checking with your scene and settings.

Firstly, I know that using AO on lights AND materials in conjunction with IDL is a problem (and isn't necessary for this technique). AO anywhere in your scene will add a lot of render time.
Transparency is also a known issue and can also slow down  IDL renders.
There may also be problems with Reflection and refraction related to the RT bounce settings in the native Poser render dialogue - there's another render dialogue by Dimension3d that has a few more settings that may help with this (in one of the Poser scrips menus I think).

I need to catch up properly so there may be other factors. I'm of the understanding that the upcoming SR1 for P8 will improve things vastly re render times, so it's probably worth waiting for this.

 

PoserPro2014(Sr4), Win7 x64, display units set to inches.

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