Is it possible to save and store a scene so editing can be resumed later?

Yes, our CE.SDK supports this important workflow.

If you use the CE.SDK UI you can e.g provide an onSave handler, in which you save the edited file to some server. On this server, the .scene file is stored.
Now it’s possible to initialize the CE.SDK e.g using the initialSceneURL  option with the scene file that was stored on the server.

You can also take a look at our documentation here and here.