Simplygon Version Change

Currently trying to start using Simplygon and I am unable to figure out how to set the UE4 Installer for version 4.21. I created a custom file, but without a destination it doesnt do anything as displayed in the picture.

Yes you just click the checkbox next to 4.21 and it will install to your 4.21 engine folder. If it can’t find it you can navigate yourself at the bottom with custom.
Then go into your engine install directory and navigate to UE_4.21\Engine\Plugins
Cut the SimplygonUE4 folder in there and paste it into your project’s Plugins folder. Then start your project, go into Edit->Plugins and activate the Simplygon plugin and restart. Should be good to go after that