I'm assuming you are doing this on a smartphone (since you said you downloaded GAIA). Try logging into your account on a computer, the phone versions can be wonky (especially Android). When you drag the .gpx file into GAIA it should give you the option of whether you want to import waypoints and/or the routes.Newbie quetion. I tried to open the KAT gpx file but google maps said it was too large. I just downloaded GAIA and it only shows the waypoints and not the route. Any suggestions?
Did you try to import the file again on your computer? or are you just viewing what you uploaded on your phone?
I use GaiaGPS and it loads the maps great and is usable from my iPhone, laptop, and my Android. Makes it a bit easier to follow, even when there was no signal.