Menu Bar Customization

I believe this is actually inserted by the IFC tranlator software module itself.

Yes thanks Thomas, understand. How does the system loads a new sub-menu item , just out of interest?

I haven't checked the detail but I assume the menu item is added at the system level rather than by a dgnlib.
The key-in 'mdl load tfifc; ifcout' will open the IFC export dialog.
Having loaded the tfifc mdl you will then be able to browse the other available key-ins.