I'll do my best to answer the questions.
a) No, Mobile PC does not come with nroute and MapSource.
nroute can only be downloaded from Garmin's website.
MapSource comes on all of Garmin's map CDs and DVDs. It is the tool that you use for trip planning and a variety of map management functions, like searching for cities, intersections, addresses, geographic features and points of interest (POIs), creating and maintaining waypoints, planning and managing routes, viewing tracks, and transferring maps, tracks, routes and waypoints between MapSource and Garmin navigation devices, like Mobile PC, Nuvi, Street Pilot, etc. To obtain an original copy requires the purchase of a Garmin map product, like City Navigator Australia.
MapSource updates can be downloaded from Garmin's website. The updates will only install if you have an older version already installed. I think this is why nroute would not install. It is based on MapSource and is treated kind of like a MapSource update. It is probably looking for an existing MapSource installation or it won't install. When I downloaded and installed nroute I already had MapSource installed (I own six Garmin map products) so there was no difficulty installing nroute.
Mobile PC is a fully featured navigation program. It has the ability to create and manage routes and waypoints (Favorites). It can search for cities, addresses, intersections, points of interest (POIs), etc. and it comes with its own set of maps (City Navigator North America) already preinstalled. So it has many of the basic features of MapSource and nroute combined in it. It is supplied as a complete standalone application.
There are more functions in MapSource that Mobile PC does not have and I find them useful. I also find MapSource much more useful for trip planning and other things than Mobile PC. But that is my personal opinion based on my personal needs and experience.
b) Your Holux m1000 or any other NMEA-compliant GPS receivers will work fine with the software-only verson of Mobile PC.
You can use MapSource to add unlocked maps to the software-only version of Mobile PC but you cannot unlock maps for it, so you would be limited to only Garmin-compatible maps that you can find on the internet. You would not be able to use City Navigator Australia with it.
Your Holux m1000 and other non-Garmin GPS receivers will not work directly with nroute. nroute does not understand the NMEA protocol. It only understands Garmin's proprietary protocol. To use the Holux with nroute you would need to get a Garmin GPS receiver or use Franson's
GPSGate software. GPSGate knows how to read the NMEA protocol from non-Garmin GPS receivers and translate it into the Garmin protocol for nroute to use. It works fine for me. It's shareware so it is not free.
c) There is no way to unlock additional Garmin maps to the software-only version of Mobile PC. You would need to use the maps that are discussed in the other threads that Marvin linked for you above. They are not locked so they can be transferred to Mobile PC software-only version (and also to the GPS20 version).
You need MapSource to transfer those maps to Mobile PC.
If you buy the GPS20 version of Mobile PC you should be able to unlock Garmin maps to it. I have asked Garmin for confirmation but I have not seen an answer yet.
MapSource is a very flexible tool for trip planning and managing maps. If you want to use topo maps and others from the internet you must have it even if you have Mobile PC.
Garmin's
City Navigator Australia looks like a pretty good product. It has features like address searching and points of interest (POIs) that you might not find in the free maps you can get on the internet.
If you buy City Navigator Australia you also get MapSource, which you need for the free maps anyway. With MapSource installed, you can download and install nroute for free, for navigation. You can purchase
Franson's GPSGate to use your Holux with nroute for navigation. It's not a free solution but it is one that gives you tremendous flexibility. You can easily add other maps as you find any that interest you.
That's just one option, but it's one that will give you a really good set of working maps immediately, a very good planning and map management program (MapSource) and a decent navigation program (nroute).
It will also let you look at the other online maps and use them with nroute. You can add Mobile PC to use with the other maps later if you wish.
I hope that helps.
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