Issues with Civ V on Steam Deck using Proton

Hello. I have tried to use the Proton compatibility tool to run Civ V in order to use mods. However, whenever I launch the game using this option, it doesn't save any changes to settings and I have to agree to the EULA every time (I have no issues when using the default non-Proton setting). Every time the game lauches, it says "updating executable", which also seems odd. I think it must be some kind of issue with the reading/writing of the config files, but saves do work which are stored in the same area. Does anyone know what could be the cause of this issue? Thanks