Thanks, Seldom, I went to the NL site and their downloads were larger and more comprehensive than the Philippine OSM site I had been using.
The map still wouldn't load using the Mapinstaller (same message) but by reading the Instructions on the NL site as to which files did what and should go where I somehow managed to drag them into the correct files on the SD card using Windows Explorer and eventually it all loaded.
As with all my forays into Garmin land it worked in the end but only after many hours of trying and not knowing what finally did the trick.
Anyhow, it is working now so thanks again.
The map still wouldn't load using the Mapinstaller (same message) but by reading the Instructions on the NL site as to which files did what and should go where I somehow managed to drag them into the correct files on the SD card using Windows Explorer and eventually it all loaded.
As with all my forays into Garmin land it worked in the end but only after many hours of trying and not knowing what finally did the trick.
Anyhow, it is working now so thanks again.