Please add your OS and Archicad version to your profile.
Answers will vary dependent upon these factors.
1. Select the doors (or any other type of elements) in the order you want to number them. You do not have to do all the doors in one try; you can do just the ones that need renumbering as the design progresses.
2. Document>Schedules & Lists>Element ID Manager
3. Sort element: choose type of element, and unique ID for each element (every door numbered separately) or Set by Same ID Criteria (Like elements all have same ID)
4. click on the Change ID's button bottom right when ready.
ID Format tab; see attached
Erika
Architect, Consultant
MacBook Pro Retina, 15-inch Yosemite 2.8 GHz Intel Core i7 16 GB 1600 MHz DDR3
Mac OSX 10.11.1
AC5-18
Onuma System
"Implementing Successful Building Information Modeling"