If you want to use either the OBBtn_KS### or the OBBtn_ExpandKS### button to automatically fill Multi-Instance Keyword Type Groups on an E-Form, you must specify a button for each instance of the Multi-Instance Keyword Type Group that you want to fill. This is accomplished by specifying the instance you want to fill in the E-Form.
For example, OBBtn_ExpandKS###_1 would specify that you want the first instance of the Multi-Instance Keyword Type Group (denoted by the _1 ) to be filled with the AutoFill Keyword Set specified (###) when this button is clicked. Likewise, if you want to fill a second instance of a Multi-Instance Keyword Type Group, a button configured as OBBtn_ExpandKS###_2 would need to be on the E-Form.
If you have multiple AutoFill Keyword Set instances on a form, clicking an expand button will expand the first open instance it finds within a Core interface. For example, if you have 4 instances, you have not expanded any AutoFill Keyword Sets, and you click the button for the fourth instance expansion, the first instance is expanded and filled because this was the first empty instance that was found.