CD Key length and format

[E'aar]

I got my key through steam (rightclick > manage > CD Keys) and it has the correct format (5x5 characters). The UI is also asking for a 25 Character key seperatred in 5 segments, which seems right. However it only allows me to type 4 characters into the UI, see screenshot:
https://imgur.com/a/cMftgrE

But then that would only be 20 characters in total.
This seems very confusing to me, what do I do?

[Vinskeet]

Weird. I was able to type all 5 characters in each field.

[wolfgang8741]

I'm having the same issue on Linux running via proton with the first field only accepting 4 out of the 5 characters while the remaining allow for 5 characters. This prevents activating the game.

The four remaining fields allow for 5 characters, but only display 4 at a time. If you select the field and use the arrow keys while the field is selected you should be able to see all 5 characters. This doesn't solve that the first field only allows 4 characters to be entered...

[Santi]

You should start the game selecting asian dynasties and u dont need to type any code and able to access full content with all expansions.

[Noah]

Same issue here running through Proton. Any way to fix this?

Edit: Changing Proton versions may help. Try Proton 5.13, it'll allow you to enter the full key and solves some of the in game issues that occur on newer versions.