That would be really interesting to know! I read somewhere that there’s an install script feature in Steamworks that allows you to run certain files (i.e. the UE4 redist installer) as the app is being installed on Steam. That could be the way it’s intended to work as well? If no one can provide answers, I guess one possible solution is to uninstall all of the prerequisites on your machine, then create a dev build that includes the prerequisites, upload it to Steam on the dev branch, uncheck all the redistributables on Steam, then download the dev branch build and install it and see if it also installs the prerequisites. However, I can’t remember if you can set the install settings in Steamworks for the dev branch exclusively or if it’s a global setting for all builds. I’m guessing you don’t want to change the settings on the live build as you’re investigating this 