Hi Markus!
Yeah, I know the message and it's impossible to get rid of it at the moment.
There are programmers out there, but so far I know, it's not possible to get this message away entirely (at least not for the screen and battery).
There are some tools to get rid of it, but after you wipe the phone, it comes back at you again.
So what causes this? Well, the screen is using a unique code, and this one need to match the code on the motherboard. If the numbers are not identical to each other, it will always give you the message that Apple is unable to verify if it's a genuine screen. Same story for the battery I'm afraid.
It doesn't matter if you replace it for a pulled screen, a new genuine screen or a copy. The codes need to match. Only Apple is able to do this at this moment.
Wish I had better news...