What is the packing procedure for shipping antique glass overseas?  I
have an antique door that is mostly glass, with a wood frame.

Ask the shipper if they pack items.  Of course, you'll ship it insured
and having the shipper pack it will ensure it is done to their specs.

I'm hearing that the glass must be taken out of the frame....

One note about insured antique items. You can insure an item for
whatever you want, but if a claim is made for it, you'll have to prove
the item's worth via an official appraisal.

Kriswrite