nice work
If only Octane had a way to generate pool caustics without texture cheating

The breasts are superb! The problem is that when she is in a position lying on the floor the gravity will take effect and you know.. . I agree about the floor though but its a lovely result.

I was thinking of this movie :) with Robim Williams-> Flabber.
http://pictures.todocoleccion.net/fot/2007/09/12/5899226.jpg
Try to play with the scale parameter of your SSS settings so you have graduate effect. Right now it looks good but too uniformly distributed almost like a simple diffuse going ...

I suggest increasing the subsurf because the black outlined edge (Terminator effect).
How about trying heavy SSS. Make it look like Flabber?

Yes you need a plane outside or the way i do it is close the window whole with a Face/polygon then assign portal material to that polygon but the expected speed up in your render should be at least 30% in such a setup. What Rico_uk said will work as a test.

evo, im not so sure that your results are great because of SSS. SSS needs a closed volume a geometry. Your leaves,grass and curtains are simple planes...the effect you are getting is mostly based on the material transmittance.

Pathtracing algorithms are always working best with open environments because the rays are shot from the camera and try to find the light sources. The more open space the easier it is to find a light source. However as this is unbiased photo-realistic render you will get far from realistic renders ...

hopefully we will see in a few months similar caustics with Octane.

Great steps have been made by you...
when i ask for the first time about MLT has been a long time (May 2010)..and today is not yet clear how it will end.
Octane Render is a fantastic program and you are great but MLT or similar is very very important (for me), and a solution should be found as soon ...

Caustics on glossy materials are actually very fast and good looking. But on refractive they are relatively slow and on pmc it needs >1000 samples until they are as bright as they should be. Also on pmc it looks like it darkens refractive materials a lot, most with a high exploration_strength or ...