returning player: Tracks and Drytop?
Can’t help with the first bit, I haven’t kept track of my earnings during DT runs (though at a guess the figure might include opening buried chests and getting lucky with champion drops).
For the second:
1. Your sPvP level does not actually matter with regard to the tracks you have available. To activate/start a track, just go in your PvP window and select one of the available tracks that you have, progress will then be made whenever you play a match – wins make you progress faster than losses, but even losses will net you progress so it’s not all-or-nothing. Solo queue gets you more progress than hotjoin, and team queue gives more than solo queue.
2. Dungeon tracks are individually unlocked by running story mode for that particular dungeon. Once it’s been unlocked, it’ll stay that way and you can repeat it as many times as you want. Each week there’ll be a dungeon track accessible to everyone no matter if it’s unlocked or not; this will rotate. If you want to get your pick of the dungeon track, run story. If not, just do the weekly.
3. Region tracks are unlocked by completing the previous region track. You start out with the Krytan region track unlocked – finish it, and you’ll unlock the Shiverpeaks track. Finishing the Shiverpeaks track will unlock the Ascalonian track, and so on. Note that you can re-run previously completed tracks for loot/skins/whatever, but this won’t unlock anything new.