Happy Friday Afternoon everyone :O)
I needed this functionality the other day, and found it was quite straight forward to add to the existing Away3D 4.0 library.
Anybody needing right click or middle click in Away3D, feel free to download the replacement classes for Mouse3DManager and MouseEvent3D here together with example usage.
The events were added in 11.2 so bare that in mind if using for mission critical functionality.
Cheers!
PS. COME ON ENGLAND!!! (for Sunday)