Hello Miguel,
I also ran into this issue when working with this component.
When looking at the JS documentation for this component I found a demo for the external drag and drop. See: https://fullcalendar.io/docs/external-dragging-demo
The draggables in the demo are constructed a bit different than what is available in the FullCalendar2 component, so I built my own blocks for that that worked like a charm. The only thing I couldn't access was the duration of the Event.
If you want I can dig up the module with the external drag and drop blocks and share it here.
Update: I'm adding the module here so you can have a look.
Regards,
Anna Lysek