I want to Prevent Grouping on drag and drop of node

I have a group, i want to prevent some specific nodes not to be able to drag inside the group. I have set the groupable property false for a node category: “alpha” which on ctrl+g is not allowing to group but is grouping on drag drop.

Also how can i Prevent group inside a group, setting group template property to groupable false is still grouping on drag drop on another group.

The general answer: GoJS Validation -- Northwoods Software

But I’m not sure I understand what specifically the problems are that you describe.

Thanks a lot Walter!