The arent any videos about but if you want to be shown check out pinkys auctions in the buy sell section and bid on a day with him, you will understand it in no time then and the biddings for a good cause.
Also take a few locks apart and read the tutorials in the european section as i mentioned then you will start to understand it. If you dont know whats going on inside the lock you will most likely struggle, a training method is to take the side off a mortice lock and replace it with perspex so you can see whats going on but this may hinder you in the future when you cant see what your doing.