I am using version 2.6.4 (just upgraded from 2.5.9). All seemed to go fine but in the admin side in the Registration Records I am having problems seeing the "Amount Due" field. Right now it is saying 0.00. I am using Authorize.net. I did a test and the whole process on the user side seems to be working well. I also tested with a live credit card and it was indeed charged.
My question is why is not populating in the Admin side.
If the registration was paid in full with authorize.net, the amount due SHOULD say 0.00. That field is to show how much the user still owes towards the registration. Also, as the amount due was not a field prior to 2.6, you will need to manually edit any existing records that show amount due incorrectly. The amount due is auto-calculated... using the registration fee minus the amount PAID. The amount paid field is also new in 2.6... so if you have no data in amount paid, then amount due would show the full amount.