OS Vectormaps on your Garmin

I’ve been following a non script (windows) route to merge free OS vector maps (.shp) with OSM and then transfer them to my Etrex; the results have been quite spectacular . I can now clearly see all OS buildings on my Garmin , useful when approaching farms . However, I’ve had to correct all the lats and lons despite the required WGS84 conversion. Does that mean the initial WGS84 conversion was inaccurate? I’ve used both qGIS and GPSMapEdit to convert.

Apparently there’s a problem with the .prj files included with the OS data, so reprojecting it to WGS84 doesn’t work properly. There’s more details here, and a link to a fixed .prj file: http://wiki.openstreetmap.org/wiki/Using_OS_Shapefiles
Just download it, and rename it to match the shp file.

Also, why not add the OS vector map data to OSM, then its useful for anyone else?

Vclaw, thanks for your reply ; yes, I was aware of the url but I’m more of a windows man; I glad you’ve confirmed there is a problem!
I’ve posted all my findings on my website www.pinns.co.uk/osm