Colleagues, I will stick to the subject due to the discussed bathroom faucet >> I have KFA RETRO.
I managed to replace the heads after 10 years, although I had to beat one knob with a rubber hammer after disassembling the entire battery because it was baked with this crap, tarnish, etc ... The solution was not successful, but the plugs are still on sale, so I didn't have to replace the entire battery so far.
However, I have another problem with the mixer in this battery.
Well, this whole mechanism of water shifting the shower / spout is very hard, so on the advice of the KFA partner store, apart from the knob and plastic latches, I also bought a plastic slider for the mixer. Everything is fine, but I don't know how to remove the old metal one.
With a large hexagon, I unscrewed the screw from above under the shower handle stand, but the mixer knob does not want to come out to pull out the old slider.
How to disassemble it? There is a screw for a flat key 14 under the mixer knob, but it cannot be unscrewed because this pin shifts from right to left and the slider is still in the socket. I thought that maybe you need to unscrew the spout and pull it out from the bottom, but this pin probably will continue to block this slider ...
My hands dropped

Maybe someone will drop some info where I'm making a mistake and how it should be removed and reinstalled

Thanks in advance!
I can post some pictures of what it looks like on mine, but for those who know the subject, they will be rather unnecessary

)
Regards
Peter