You cannot load a version into the nav if it is already fitted - because SW version is the same, therefore there is no change, therefore no need to load.

either
a) load an older version first, then your modified SW
b) change the version number on your modified SW to a higher version (the correct way)

Change version in SW_rel.tbl (text file)

Yes, you can downgrade to the older version and then upgrade once again with uploading required languages....

OR you can upload your languages without downgrading - for that you'll need special soft (NavCoder for example http://www.xoutpost.com/navigation-sy...-released.html ) and upload required modules.

If required language is alredy exist in language pack of your navi but you made some changes and want to upload it to your navi - downgrading and upgrading (without soft) could be used. If you trying to upload language which is not in language set of your nav - soft is required definately so you can use second method.

BUT BEFORE YOU START - read about specific fof MK3 devices!!!! It's very sensitive to navi soft!!! And everything what you are doing is for your oun risk!!!

Good luck!