Today I received the answer I was waiting for, as said before in this thread the licenses for Navicore are perpetual, so if you bought the navigation kit for N800 (like I did) or a license for Navicore personal 2007 you can contact Wayfinder and ask them to extend the license expiry date. The licenses bought for the built in map application in OS2008 (Wayfinder navigator) are limited to three years.

Thank you all for this really useful thread.