2005 UK Model Spirit Navigation

Hi all. I have been driving a 2001 Prius for a long time, So I deicded to give that to my wife because she loves as much as I do but I now Love my new used 2005 Spirit Car. I bought it just recently and Have ofcourse a lot of questions so wondering if you can help in this first question of many.

The Navigation DVD in prius.

Currently it said I have the 2006-2007 Ver 2 in the DVD. I still dont know what that Mean.

So my first question is how do I access the DVD underneath the seat. I moved the seat all the way to the fron but still cant see how I can remove that cover.

Is there a spcific instuctions that someone can guide me how I can access the DVD please.