Hi Bob,
Thanks for the link. The GPS info PM stores is correct, so the problem really is with the viewers. That said, there might be something PM could do to “help” the faulty software.
The ACDSee version stores the info in both the EXIF and XMP format (EXIF:GPS and XMP:XMP-exif groups respectively), where PM only stores it in the XMP. I think there's the issue; the other viewers incorrectly parse the XMP (or so it seems).
Now I'm not sure how easy it is for PM to also write the EXIF:GPS:GPSLatitude, EXIF:GPS:GPSLatitudeRef, EXIF:GPS:GPSLongitude, and EXIF:GPS:GPSLongitudeRef tags, but that would likely fix the problem.
Cheers,
Hayo