Incase anyone is interested... I found some info on using includes in the navit xml file. So I've added someinfo to the wiki about switching the OSD items with an include line which pulls them in from a separate navitOSD.xml file. I'm hoping this will make it easier for me to try out various OSD layouts and drop them in place without having to edit the file by hand.


just to make life a little easier I also decided to create a page off of my blog
http://danielwould.wordpress.com/navit-stuff/
which contains some layouts as just blocks of OSD xml with no interspersed text so that it is easy to just cut'n'paste ones into files to play with.Sadly neither the navit wiki nor my wordpress blog seem to want to let me upload xml files, or even zip files. So this seemed a workable solution so far.
At the moment I just have my original layout, Lemmyslenders generally nicer layout. And my slight tweaks on that to satisfy my need for bigger text ;-)