How to change map download thumbnail

[ThatGreenSpyGuy]

Seriously though how the heck do I change it. Neither the edit overview page nor the post download update page allowed me to update the thumbnail for the map :/

 

[XEnderFaceX]

On you'r Map Page, click "Edit Download Icon" then add you'r Screenshot

 

[ThatGreenSpyGuy]

Thanks so much!