The Edge 810 works as a USB mass storage device. So when you plug it in, it will just appear as a disk drive. Then you can copy any files on or off, no need for any special software or drivers etc.
Its easy enough to copy your recorded activities off, and do a manual upload to Garmin Connect or Strava etc.
Plus there's plenty of websites that will let you draw a route, then export it as a GPX or TCX file to copy onto the Garmin.
Or for on your own computer, Turtle Sport is not bad for viewing your rides.
For more detailed performance analysis, you could try GoldenCheetah.
For plotting routes, maybe QLandKarte (it seems it has now become QMapShack).