 So you wish you could control the thumbnail for your Unreal project, not a problem. First you need an image that is 192 by 192 pixels big. Then in Unreal, go to Edit and under Project Settings, click Project Thumbnail, and select your image. You're done. Now when you open a project, it'll be a lot easier to see which project you want to open. Hope that helps and as always, hope you have a fantastic day. Now, see you around.