The Spaced-Out regolith asteroid seems to function identical to vanilla where I've built bunker tiles in upper most tile-space (first line below the no build zone), and regolith tiles naturally only stack two tiles above that into the no build zone.
In my game, there is a repeatable apparently indefinite game lockup bug when duplicants path 1+ tile(s) above the build line. I have made the game lockup 4 times at different in-game times by simply allowing the duplicants on the regolith asteroid to walk on the bunker doors built on the edge of space and path on any regolith tiles on the bunker doors. I made this save just before the bunker doors open with duplicants waiting to work on the recently fallen regolith sitting in the no build zone. It locks every time a duplicant steps on a regolith tile and visually their head isnt fully rendered.
-Open bunker door built in upper most tile-space
-allow duplicants to step on a one or two tile stack of regolith sitting on a tile built at the top of build zone (edge of the no build zone in space).
Of note, there are 3 mods used: Big Zoom, Pliers, & Blueprints.
UPDATE: I have updated this post as I have now disabled all mods so hopefully eliminate that variable and am able to reliably repeat the lock.