In my game, the shaders for textures are not working at all, no matter which detail I set.
I even trief some config file workaround, doesn't help either.

I am playing Spore on a notebook with switchble graphics, Spore is set to the gaming GPU of it.

Still, everything that should be shiny or something is just bland and flat.
Any ides what I could try to fix it?

This worked for me:

https://forum.spore.com/jforum/posts/list/81238.page

To test it, go to the Creature Creator, and then to Sporepedia. Find a creature made by Maxis called "Antube". Load it, and switch to Paint Mode. After the textures all generate, the creature should look pretty shiny -- see attached image.

(And remember, be sure to thank Mr. Goffin for all things shiny in Spore!)

Well, big thanks for Mr. Goffin, and more thanks to you for bringing this to my attention.
Thanks a lot.

I tried that method before as I saw in my files, but I did not use it on both folders that have to be changed, the version you linked clarified this, so I finally found the second folder, and now it works and looks good.

For me the following Folders had to be changed (Gog Version):

Spore/data/config
Spore/dataEP1/config

Thanks.