This map and the other Trials maps aren't available for offline play, but hosted on the "Testlab Trials - Defrag" and "MOD Movement Prctc" custom servers. You can connect there any time, vote the map you want and it will auto-download.
Did you see the official movement tutorial? https://youtu.be/xjVmUhmnvVU
I use shift-dodge, Chatouille (the best Trials player) uses double-tap dodge - both work fine.
IMO shift-dodge is easier to get used to, double-tap is for UT veterans.
It also took me days to learn the various wall-dodge jumps on foundation. But it's worth it. Movement is at least as important as good aim in this game.