Will the system work without the Nav Comp?

[noddyunplugged]

(Posted this in the E53 general forum too, oops)

Hi all,

Please read the post before replying to its title LOL!

I'm in the process of buying-in all the parts I need to fit widescreen sat nav into my 2001 4.4 sport (that currently only has business radio and changer).

So far I have a wiring loom of a 2004 manufacture date (apparently. But has flat pins anyway) and a Dec 2005 BM54 radio. I'm looking to buy the screen next, at some point.

My question is: will the radio, cd changer and screen work "for now" without the nav drive unit installed, or will I have to wait until I have everything before I can install/make use of anything?