I can't get Garmin Express to open and register my Edge 800. It works on my wife's Mac Book Air but not on my MacBook Pro. I have upgraded to El Capitan. Removed all previous G Exp folders and tried reinstalling using both Safari and Firefox. After downloading G Exp I click on the teardrop icon and then a rectanglar icon opens but just hangs on the screen. I have 25 gb of disc space and 2gb of ram. Patience is wearing thin. Please help.