When you add a reference object (BO_ref) to an existing BO (BO_A) that is a member of a business object GROUP (BOG_Z), saving will NOT detect the group and NOT prompt you to ask what to do with other group member objects.
Workaround:
. create a dummy text attribute in BO_A, save and apply to other group member objects as required
. change BO_A.Dummy attribute from plain/text to BO_ref, when saving you will be prompted to appply the change to the other group member objects.
Bus. Object Group - adding a reference object
Bus. Object Group - adding a reference object
Build 1246 - Windows/Mysql