I have only played with a few GPS camera files and here is what I did.
The GPS data is stored in the EXIF data that is part of the picture data file.
The best way I found to display the data is to use a "free" photo display program called IRFANVIEW.
After you load the photo into Irfanview,
click "EXIF" button
then explore the GPS features.
i have recently purchased a tz20 camera and am disapointed that the gps location does not show on downloaded picture files