Missing something on a magix system trying to forward ext calls to outside phone number. Have allowed trunk to trunk transfer from winspm, but at the 4424 phone after pressing forward and enter 9 the display drops out and goes back to date and time. Other ext phone work but are in a different trunk group.

Did you allow Remote forward for that ext?
Did you give it a dialout pool?(which is dialoutcd in Winspm).This would be the same pool group it normally dials out from.