I was hoping to see an image with a render to decide if I should download, that's why I asked.

I downloaded it and opened it. Here's my impressions:

a) the render settings are set to "user settings" and "compute physically accurate caustics" are not on. So, the main theme of the image (caustics) are not seen unless the user changes this. This puzzled me a bit. I thought that a newbie could have problems.

b) because of the above, I opened the material and saw that you simulated caustics by using variable transparency. So, this is really fake caustics, not physically accurate caustics. I must say I didn't like the result very much.

c) in the render settings, other settings are not too good and, again, a newbie could have problems: the advanced effects settings are too low, the optimize volumetrics is on which decreases the quality of the volumetrics, optimize last render pass is on, which decreases quality.

d) In the atmospheric settings, light tab, the quality settings are set to zero. This unnecessarily increases render times. I typically use negative values (-3 or -4, depending on the situations).

e) the angle of the sun and of the volumetric light you used are not the same. This causes light inconsistency.