About 290 kb:

I didn't understand what you wanted to tell me with the hungarian link. 
I am going to post a photo in the theatre thread with the actual capital. It will be about 230 kb at the moment, I did something wrong with the actual columns (they are too big, in fact I repeated them 3 times, I didn't know anything about components at that time
), so I can reach the 500 kb (but I don't think that happens).
Ok. I thought you had post some links in hungarian, but I only saw the spanish ones that you showed me some time ago 
This is the actual situation of the capital:

about 230 kb
Yes, I saw them...

But my hungarian is a bit rusty, sorry 
(I know that is a offtopic, but my chorintian capital is taking the right way
)
I told you about balawat, no?
Why don't you register into their forums to ask them for help?
They are spanish, like me, but try to speak them in english. Perhaps they may speak with you. They use 3D Max:
I have told them that I will register there when their work about the roman theatre of Cartagena is public, in a few months (now is closed).
Your work is impressive Gaieus 
I am downloading the videos now.
I have tried to start a chorintian capital, that's what I have done untill now:

I used a photo of a capital (Gaeius, you know what I am talking about
).
I drew the figure over a photograph, and then I did something like a tutorial I can't find now, I used intersections to make it. And then I adjusted it manually.
The size now is 147 kb, but the photo is 55 ,kb. I believe I can use 500 kb for the entire capital.
I have to make a corinthian capital in sketchup for my roman theatre... I am afraid of the amount of work (I am not an expert in sketchup).
I have downloaded your sample to look for inspiration... (Don't worry, I would never use or modify yours, believe me). I hope is not difficult to do it, if you know how...
It's a great work, congratulations.
Now I know that is a bug, but is not my fault. The light leaks appear under Photon Map mode, not with the others.
The images below show you what I say, under different presets.
PHOTON MAP FINE + AA 0.3

PHOTON MAP FINE + CAUSTICS + AA 0.3

RAY TRACING HIGH + AA 0.3

PATH TRACING HIGH + AA 0.3

After doing a quick test, Metropolis Light Transport seems to work well, too.
So now I am not nervous, and I know that I can continue with my work. I was doing it well.
Yes, I didn't make any changes to materials. I have no idea about this 
I am looking for a solution in Google. As my english and knowledge are limited, I didn't know that the key word was "light leak". If I can't find anything, I will post my problem in Kerkythea Forums.
I oriented the faces in the inma cavea, (the blue area) and the problem persists:

I suposse it's a problem of materials in Kerkythea... I don't know 
I am examining it, and I see that al the component has a texture, not "A face, a texture". Or something like that.
Must I begin to define every single face?
I didnt' modify anything in kerkythea, I am a newbie with that program. 
So it's an isue with kerkythea, Am I right?
Respect to orient/reversed faces, I suposse I must modify every single surface and give it a texture. I'll do it when I finish.
¿How do I fix this Disaster? 

Yes, I know that there are reversed faces. But look, these "ghost lights"...
I made it under Kerkythea, perhaps I should ask this in Kerkythea forums. I believe that there are not "holes" in the model... I don't know what to do 
I like potatoes,
and ketchup made
from tomatoes.
Sorry, but my english is very limited... 
The textures are not definitive. In fact I hope to work in a more worked ones.
But the colours are intentional. Forgive my limited english vocabulary, but the yellow stone is made from "sand stone", and the grey - blue from limestone. But the colours are intentional.
And yes, I have rendered it in Kerkythea before. As I am a newbie (doing a thing very complex, but this is my first serious project), when I see in the rendered image something wrong, I check the properties of the face and fix the mistakes.
That's what I have done until now. And not, I don't know what those commands are. In fact I didn't want to see the texture stuff until the model is finished.
This evening I have been working with gimp and a wall of yellow stone. I will make it tileable, but at this moment it requires a lot of clone tool.
And thanks Anssi, for your interest.
Some work in the summa cavea:

I am just an engineer, not archeologist. So I can't help you 
On the other hand, the more I read about your job, the more I understand that my idea of a modern archeologist is turning more and more technical. You need to know about topography, geophysics, GIS, CAD... Is like if you were turning more like a Mining Engineer.