Hi Tyre,
On your nav screen in the upper right hand corner should be a small box with the corner of a globe. Are there any green dots appearing in that box? If so, that is an indication of how many GPS satelites your receiver is seeing a signal from. If not, then you aren't receiving any GPS signals and the system isn't able to guide you.
You are probably aware of this, but the MkI has a separate GPS receiver module that is a completely different component from the nav drive. With the MkIII the GPS receiver is built-in and the antenna connector would go directly from the antenna to the MkIII drive unit.
It's likely that the problem you are encountering on the MkIII will also be present on the MkIV, so let's see if we can get this figured out. There's a diagnostic screen that you can access. See
http://www.xoutpost.com/showarticle-164.html for details.
I'm also going to send you a PM with a source that has a copy of V15 and V18 OS.
and let us know how it works out.
Jeff
:xoutpost: