I kinda solved the problem. I soldered a connector between the controller and mother board. Now I could reconnect the controller "for real". It stops pulling to bottom left corner after reconnect, but after powering the console again, it starts messing around again.
I'm beginning to think there's something wrong with the controller board. I relocated some components and maybe I messed something up. I would be very pleased if somebody could take some pictures of the unmodified board from both sides. I'm using Logic 3 turbo/slow controller.


(Click pictures for huge ones)
E: I realised that I had soldered R to wrong place. Now the neutral position reset works (hold R, L and Start) and after that it works like it should. The problem is that you have to do that every time you launch the system, because it wont remember it next time so I really would like to fix this ones and for all.















