Well, I resume the history.
I was playing in a normal 1.11.2 world, completely vanilla.
Then I decided to install forge, with Lunatrius core and Schematica mod to build a great big thing.
Then, when I built It and I wanted to go back to the vanilla 1.11.2 and I enter the world, all the observers are broken. They are stuck in the *Gives signal* Mode. You have to break them or move them with a piston in order for them to update.
I tested if updating to mc vanilla 1.12 it would update, b