I think we connected with you via email, but just for everyone following along: Loading a blank file named reset_to_factory_defaults.dfg will reset most things to the way they were at the factory. That has the caveat of not working with displays that have an OEM controlled configuration on them. Now the RV12 has settings packages that Vans provides, but they don't have the configuration controlled (ie locked). That means that even if you don't do the above reset, you're able to just go in and change every setting to suit your aircraft (you'd need to do that either way, of course).
There are a few things that don't completely reset when using the above file, like the SkyView Network configuration, but you'll end up redoing that when you configure the display with your new modules. Additionally, in any installation, whether or not you're utilizing a truly new out-of-the-box display or whether you're re-purposing a used one, you want to make sure you go through every setup menu / setting to make sure everything is configured for your aircraft.