@pekka3 in order to address both questions, you will need to resync registry as Richard has pointed out in the other thread for the Material Browser and MDL Material Graph extension to show up before you can enable them. it could take around 5 or 6 minutes for this process to complete. keep an eye out for the blue text in the bottom left of the extension manager as it will show the state of the sync. when it’s complete, it should read something like “Registry Synced”
Kit full app? I would advise you do not use that but just use the normal USD Composer. The “full” kit app, is not named because it is full of extensions.. There is way less turned on it that app than just normal composer. Kit full app is more like the “kit base editor”. Very minimal.
Our best app to use is always USD Composer. If you want that to be “full” just add a lot of extension to that.