How was this done ???
Have a similar issue - have added an extra field for "delivery email" - the field appears, but the content is empty !
- it shows correct in VM "shoppers" and in frontend ???

Hello, Extra fields on invoice displays info stored with particular order. So is not displayed users's default info, but info specific for order. If you open that order in VM Invoice order edit or VirtueMart, field is probably blank there. Info must be entered in order to be able to show it.

Clears it :o) BTW, just info...if I choose "shipment addresses" and say yes to "update user info" - if generates a whole new shipment address - and can´t delete it anywhere in VM yet :o) Have a much more important issue - had to post it in "presale" ! It´s critical for my installs - cant add customers !