And what about the UOG? It exist only to explain what wasn't explained in the game. But Compilation Haters still ignore it, believing more in their own theories, than in the word of SE.
Square Enix haven't made a book explaining Final Fantasy VII; only Final Fantasy VII: Advent Children have been explained. So I've already explained why the UOG is ignored by the likes of me.

maby people like what they think better
In some cases, indeed. Certain theories prove that...

The problem isn't with people that belive in their theories, but in people that try to convince us that their interpretations are the absolute truth, and that SE is wrong.
If The Compilation is the same as Square Enix to you (regarding answers to the plot of course) then yes they are wrong, because The Compilation is retcon. Like Ryushikaze said, that doesn't make it less official. But that was the point of this topic in the first place, to show you that official by no means is a guarantee of canon.

Like I said, many believe parts of FFVII to be unsolvable. However, most of it makes perfect sense once you have played the game 20-30 times, written down all dialogue, tested different versions to see where they get shattered, and then finally, realising one version of your FFVII storylines make perfect sense.

It is a slow process and many players skip all this work, stick to one of their theories then begin entering discussions on forums. It is because of this difficulity of deciphering the storyline there are so many theories "out there", and that is also why people generally never agree with each other when a theory is presented.

Square Enix used this opportunity to make a Compilation of it all. They have made a fortune or two by doing so.