Result: 2 level group move to location, that it had before 6 step. But if 3 level group have isSubGraghExpanded = true, it works well. All layouts isOngoing = false.
In your app, do all of the nodes and groups have real locations assigned in their model data (even if the node starts off hidden), and do all of the nodes and groups have bindings on the Node.location property?
We can reproduce the problem, and it looks like a bug. More investigation is needed.
Thanks for reporting the problem. Can you avoid the problem in your app if you disable the AnimationManager? You can do that when you make the Diagram by:
Could please you try the beta 2.1.15 release at https://gojs.net/beta/release/go.js (or go-debug.js) and see if your app works better even with animation turned on?