Issue with .GPX input formats

Hiya,

I've got a VIRB Basic and ran a gps tracker app while skiing yesterday. I was trying to import the .GPX trace into the VIRB Edit suite and use it with the footage I shot on the VIRB.

None of the .GPX files I tried would import into the edit suite - except one that I tested which had been created with the Strava Android app (last year) and then exported via Garmin Connect.

Why do some .GPX files work and some don't? Is there a way of processing them so that they're compatible with VIRB edit?

Cheers,

P