Font sdk 1.2.1 vs 1.2.2

With the new SDK, several new fields are read (xoffset, xadvance, ...)

The Simulator work great, but when I test is on the watch (920xt / 6.10 or 6.20), the font display is very strange (pixel added, irregular spacing, ...)

Could you give us some precision about fnt fields usage?
(http://www.angelcode.com/products/bmfont/doc/file_format.html)

Regards,