Dupes froze after doing some actions

I think this is due to lag. Are you using super speed from the debug mode ? If this is the case you maybe should not use it because the dupes hanging out a bit is the "pathing" and "find a task" algorithm that takes more time to resolve. The simulation goes on but the algorithm can't make it in time. 

The preview builds are always more laggy than normal build because of active logging (that are not active in normal builds) and the fact that devs activated some data sender so they can see a lot of bugs without users reporting them.

You may want to tune down the speed or wait for the full release of RU to enjoy the game fully 

I've just used fast speed in normal game, not debug mode. And as you said, I'm not expecting good experience when playing beta release right now, just think it's kinda like a bug and want to report it

This is a duplicate bug, or at least similar to:

 

Same issue, "rocketry" branch only.