Good Evening Room from a very wet Central Portugal!

My very good friend has just recently lent me his 2002 BMW 530d as I've had to bid farewell to my last car - a lengthy story involving import taxes etc...

It's very, very nice and he's offered to sell it to me for a reasonable (well, as much as they can be over here) price.

My question is this... I notice in the boot there's what looks like an MK2 navigation unit - it has no CD in and the power light is flashing orange.

I've been pondering with the idea of whether or not to trawl through the internet to try and download the navigation software required.

My question is, where would I go, what version would I need and can I truly be sure that the car is equipped for it?

I know that's a stupid question, what with the unit being in the boot and all, but there's no mention of navigation on the menu screen.

Is this something that only appears when the CD is inserted?

Sorry to ask so many questions and for being such a novice - I imagine the more experienced amongst you are rolling your eyes as I type this!

Any help you can give me would be really very much appreciated.