New beta build! https://wiki.arcengames.com/index.php?title=AI_War_2:Multiplayer_Alpha_And_Beta#Beta_2.755_Hotfixes
You need to use the current_beta branch on Steam or GOG to play this one. If you have trouble with it, there is a most_recent_stable_beta, now, too.
Right now the most_recent_stable_beta points to 2.753 still, because the prior build was anything but stable. Apparently I was very tired yesterday evening, because not all of my most recent changes for part of that build even compiled, and I forgot to code the last half of one. That was... a first for me, in 12 years of doing this.
But in terms of what caused stability problems, that actually had nothing to do with my oversights, and was simply a matter of the new "states of matter" feature that is mostly DLC2-oriented having some "this is new and large" standard kinds of issues. Being able to get all our new unit mechanic features in for DLC2, and pave the ground for some of that for DLC3, as part of the tail end of this beta period really speeds things up and will pay dividends for stability in the main branch in the future.
Beyond that, GregC discovered that the 4th tutorial was un-completeable in the beta branch, so that's solved. Sigma7 and Ryulong had found a strange case in the beta where your flagships could disappear, or even your home command station, now that you can mark down by refunding fleet upgrades. These were not new issues in the last day or week, but it's great to have those fixed well BEFORE we go back to the stable branch.
Enjoy!