Tom, If you entered in a class under 'not running in your usual class', Motorsportsreg will override the Timing Computer in regards to what class you drove in last time. However, these next few registrations will be a bit messy with all the changes.
It is still absolutely advisable and necessary to check that you are in the correct class posted on the Trailer Door the day of the AX. We revised some procedures in AX Pre-Registration which should make it modern, easier and nicer for all - We'll post a review of them soon. Next, we will tackle some of the issues with the Motorsportsreg system. There are fields to fill out on the registration page that need to be mandatory, (example - new 2012 class -
unknown will not be an option 
), and fields that also need clarification (example - if you request a particular car # it may not be available in our system). We're making pre-registration better so that the new team has less busy work and an improved experience!