[OSM-newbies] Slippy map with route overlay?

[Dave F.]

Richard Weait wrote:
> Right.  Cyclemap makes this look deceptively easy.  Beautiful and
> functional with a lot of technology going on in the background.
>
> How about something a little simpler than rendering your own map with
> custom rules.  Rejo made it easy to put a default OSM Mapnik map in
> your web page, and then overlay your gpx track file using openlayers.
> This would relieve you of having to do any custom rendering, but you
> will have to record / create a suitable gpx trackfile.
>
> The details are here.
> https://rejo.zenger.nl/topo/embed-osm-and-track-in-webpage.php
>
> An example is here.
> http://weait.com/content/easy-osm-your-gpx-tracks

Thanks
This looks like what I might need. I'm going to look into it in more 
detail now.

But could you help clarify a couple of points to get me going:

1. kml can support ways of different colour/width etc. Do they show up 
as different on the overlay map?

2. For me to test is there a way to get iframe/src tag to accept a local 
file instead of http? eg c:\My_KML_Files/Path.kml?

Cheers
Dave F.