Hi there Stu
I am currently out at EFT, and this is what happened to me and as far as i can tell happens to us all.
You get your fingerprinted at the embassy, but only your index ones (I think). When you arrive here, you are fingerprinted by the immigration people (as per your interview) and sent to a room while they get confirmation or somthing like that. They will come and give you your passport bcak and off you go. Charlotte will organise you fingerprinting at the local Police Station it cost me $10 and it's done in ten mins or so. This is a seperate thing as the smbassy and innigration ones are electronic scan, at the police station its the good old fingerpring card.
Hope this helps
FF