It's been a month and the demo update is not yet ready. I have been working on both the UI and the save/load system and both are making progress, though some bugs took forever to find and fix. And saving/loading an entire galaxy with tons of dynamic data is anything but trivial.
Plus real life, etc. - I am a solo indie develope with a day job that has nothing to do with game development, so there is that.
The progress I made over the past weeks has me hopeful that an update will be coming soon. Save/load is not important for the demo, but vital for the Early Access release that I want to make soon.
So keep watching this space for more updates and a new version soon.