If you select all the variables within a Group and move them to another model (a very nice feature by the way), the variables move, all the formulas are adjusted appropriately, but the Group remains in the original model with zero variables. Furthermore, you can’t get rid of the Group. Even if you add a bogus variable and then delete it, the Group remains with zero variables. While you are at fixing this trivial bug, maybe add the ability to move a Group with all its variables - you can already move a group of selected variables, why not the Group container along with it?
I’ve now discovered the “ungroup” option for a Group container. This gets rid of the orphan Group, so problem solved! But there is still an inconsistency. Normally if you have a Group and delete all the variables in the Group, the Group disappears. To be consistent you should allow the creation of a zero variable Group and only get rid of it with the Ungroup option.
Thanks for reporting this!