Entering Destinations On Nav While Moving

[dclexus]

I recently upgraded my map DVD to version 6.1 from 4.2 on my 2005 RX330. On the old map I ws able to override the lockout by using the Volume screen with access to the override menu. Now with the new map DVD, I cannot access that menu. Is there a way to override the system with the new DVD? Alternatively, can I go back to the version 4.2 or is the upgrade irreversible?

Thanks

Steve