OK. Creating new routes ... If you are into some self abuse, you can find much of what I'm about to say at https://www.topografix.com/gpx_manual.asp
. There is a more recent version, but it's harder to read and adds nothing to this particular conversation.
First, a word about 'routes'. A long time back, the *.gpx file 'standard' (GPS Exchange Format) was released to try to create a common base for all GPS units to share 'route' information. These are human readable files in a unique sort of XML format.
A *.gpx file can come in one of three flavors, though a few packages hybridize them with two flavors at once. TomTom uses only ONE of these flavors -- perhaps the least useful, but at least it's a standard.
I'm going to describe each of the three types, starting with the one that is closest in nature to your TomTom *.itn files. The reason for this explanation is to provide a rationale for the tools you will now need to create your routes. It won't likely be any of the tools you have used before.
The first flavor of *.gpx contains 'waypoint' information, and each location identified in the file with a <wpt> designator. When following a <wpt> file, the device is expected to manage its own navigation, only concerning itself with hitting each of the <wpt> locations in the sequence in which they are specified in the file. Sounds just like an *.itn file, doesn't it? [For no good reason that I can explain, TomTom does not support the old *.itn files except on their Rider (motorcycling) series of devices.]
The second flavor of *.gpx contains "routepoint' information, and each location identified in the file with a <rtept> designator indicates a mandatory point for a turn in the navigation. Rather than allowing the device to make its own choices about how to get from A to B, it must follow the turn by turn directions of the <rpt> entries in the file. Therefore, this type does not allow the device to take into account current traffic situations, etc.
The last flavor of "gpx contains 'trackpoint' information. Think of this as the 'breadcrumbs' approach. A track is created of <trkpt> entries in the file that the device must follow, come hell or unexpected high water. They are often built using a timer that records a traveled route's location every X seconds. Lots of little dots marked along a route on a map, each to be achieved one after the other. Unfortunately, this often very large and less useful file version is what TomTom currently supports on these new devices, including the 520. That said, a tool that will create a <trkpt> style *.gpx file can also be used similarly to other types by spreading out the track points more than is typical. You can place them at intersections or waypoints alone, allowing the device some flexibility in creating a route. However, if you create these routes using your 520 (it has an option to follow your route and create them as you go) for later use, be aware that it will create a trackpoint every 1 second, which will allow no deviation whatsoever from the route you take.
All of the above to say that not every took that can create a *.gpx file is created equal. Not all know how to create a <trkpt> style *.gpx file.
The actual content of the file needs to look something like this:
<trkpt lat="47.72051" lon="9.39098"></trkpt>
<trkpt lat="47.72064" lon="9.39099"></trkpt>
I believe all of the following remain viable candidates:
TYRE and its older brother whose name I cannot immediately recall (see http://www.tyretotravel.com/
) will create a decent track file.
Google Earth using this method >> http://livelikepete.com/how-to-create-your-own-gps-tracks-using-google-earth/
Here is an online site, but I believe it requires at least registration >> https://www.gpsies.com
(just create track, don't add waypoints)
I am sure there are other methods to generate them as well.
Once you have a *.gpx file in <trkpt> format, now using the fourth icon from the top, you upload it to the MyDrive Web server at this point
and select "IMPORT A GPX FILE"
However, beware of the baloney in the next screen that you'll see ...
as the word "any" is about as untrue as it could be. The majority of *.gpx file creators do not generate the requisite <trkpt> style files!
At this point, you can "Select File" from whatever you have created on your PC. It will then sync to your 520 the next time it connects to TomTom's server.