[Plugin: Register Plus] Invitation Codes

Hey,
This is the most awsomest of plugins. I wonder if you could tell me where the invitation codes are stored or give me some direction on how I can input/create lots of codes at once rather than manually put them in…
BTW I can generate the codes, it’s just inputting part…
Register Plus really has made wordpress a usable platform for me so thank you.
G – tutortunes