Does that mean that there is another teacher panel and other Desmos activities with more features / possibilities? Or are they beta or alpha type things?
They are only for proprietary activities made by Desmos. I asked before about this (can’t find the thread though), mostly all the different export sinks.
Yeah, the export sink won’t do anything for the activity itself, you’re not missing out on anything. It works with some internal tools go give us more insight into the activities themselves.