I recently had to make a back-up of the BaseCamp data due to the computer becoming unstable!
Fortunately I made two back-ups, the first a file copy and the other via the Back-up function.
While the Back-up function backed up most of the data - the routes etc. perfectly, it did not transfer all of the track data. It missed some of the details on the track, which is a shame as I am a sad sort of person!
If the programmers can correct this, I would be grateful.
If you do not use BaseCamp to store your track data, then this is not an issue. If you do then I would recommend transferring the data via file transfer. I am certain the file structure is mentioned somewhere here or greater minds than me can tell you.