I already did this before posting here. It didn't solve the problem.
Unless I need a new save from the beginning. That's the only thing I didn't try
Well, no matter what, according to the tracelog that IS what the problem is. The last line (or near it) in your tracelog you posted that contains the source of the error states that it cannot figure out which variable you are referring to between the square brackets. You see, in the Python/RenPY coding language you embed a variable inside text using square brackets. let me give you an example...
lets say you have a variable (it's a programming method to contain information like numbers and text) called "name" and you set name equal to your name "Zaitsev77"...
$name = "Zaitsev77"
Now lets say I have some text in the game that says hello to whatever name that is... it would be:
"Hello [name]! How are you?"
Now in Python/RenPY (the programming code the game uses) it sees the brackets and thinks "he has a variable in there, let me check what "name" means, and it will, in this case, see "Zaitsev77" and it will display that on screen. Well, in your case, your folder name contains brackets, and when the game tries to display an image, which is contained inside one of your folders, it runs into your square brackets and thinks "hey, there's a variable in here, lets see what it means", and when it checks, there is no such variable that is named inside your square brackets, so it gives you an error and can't continue.
If you have a saved game, it MIGHT contain the same information. You may have to restart. But the square brackets are absolutely what your problem is. Your tracelog error said so. There is no doubt about it.