I am still going to insist this issue I have N810 btw

Yes I am sure your Maemo Mapper does work fine as this setting I am talking about relates only to the network connection that is established when AGPS starts if no other network connection is available. If you don't want your 3G/GPRS connection to autostart then you wont notice anything. The setting does not define the GPS module or connection to a GPS module. In fact if I use external GPS module I do not change a thing in AGPS settings.

When you use internal GPS with Maemo Mapper, yes you leave the GPS blank in Maemo Mapper settings as described in Maemo Mapper docs.

This is what happens with my N810 when starting Maemo Mapper (or any other software using GPS)
1. Start the software
2. GPS (internal or external, I have both) defined in Control Panel and/or software in question starts.
3. AGPS notices no network connectivity yet it needs to download AGPS data, Packet data is allowed in AGPS settings, therefore it starts the packet data connection defined in Preferred connection using the phone defined in Control panel. If I have Wifi connection or existing GPRS connection the preferred connection setting has no relevance.

If you disable packet data in AGPS settings then the preferred connection is grayed out. Yet Maemo Mapper downloads AGPS if you have Wifi. I think this clearly speaks for the fact that the preferred connection relates to data connection using phone. When disabled AGPS will still download AGPS data using Wifi but will not autostart GPRS packet data when wifi connectivity is not available.

I base my interpretation on this issue my own experiences and to instructions at http://betalabs.nokia.com/blog/2008/...n810/#comments comment #19. I believe the commenter Marko is AGPS developer so I value his instructions highly.

I have tested this with two phones using two different operators data plans. With these combinations it makes a pain to change phones, first I need to change the preferred connection to a different operator. Then from control panel change the phone.

I also have external GPS module but usually use the N810 internal as I find it acceptable with the help of AGPS. I get consistent GPS locks everywhere within 60 secs when using AGPS with preferred connection.