How do I add picture to my Mod/Tuning Pack?

Hi.

Made my first tuning pack using the guides on the AOE4 support page which were extremely helpful but I cannot figure out how to get a picture added to the background.

Any help with this much appreciated.

There you have a good video .

You just need to click on show in game folder and replace the mod.png with another mod.png photo .

The photo needs to be 16:9 , and it needs to have a resolution using a multiple of 4