Add-ins can later change the ButtonText name by responding to the QueryStatus method. If the text begins with "#", then the rest of the string is an integer that represents a resource ID in the Add-in's registered satellite DLL.
ppsaContextUIGUIDs is used when the Add-in is not loaded and thus cannot respond to the QueryStatus method. If ppsaContextUIGUIDs is empty, then the command is enabled until the Add-in is loaded and can respond to QueryStatus.
The Add-in can receive invocation notification through the IDTCommandTarget interface. A button can be added by using the OnConnection method of the IDTExtensibility2 interface