Hey, I think it may have mistakenly said there was an update because the currently-available build is still around a year old. I didn't realize that disabling/re-enabling the visibility of build would tell people there was an update... Can you let me know what the first boss you're referring to is? The game only saves in the Hub areas, so depending on the story, there are sometimes multiple battles before the next time the game saves.
If you are interested in a new/updated build feel free to reach out to me in DevTalk. I appreciate the feedback though! I think some of it, like the use of Unity default UI assets, has been mostly taken care of. The battles are still KB-only though. I think that's the only part of the game that is not fully playable with either mouse or kb now. Since there are so many potential actions between boosting/swapping/polarity/etc, I was never quite sure how to handle the use of the mouse there.