Update: I got all wrs except for one, which I believe is cheated (can you remove it?) Also, am I allowed to give myself unlimited fuel for runs, or are my runs with infinite fuel considered illegitimate? If it's not allowed, I'll try to beat my times legit. Additionally, I gave myself all the pro cars by changing the save file, but I don't think it gives me a competitive advantage.
Progress (default setting runs):
Jumps 2: Beat 2nd place (3rd if you count the 8 second time) but not pb
Hardest map: Beat my pb
Speeeeed: Beat 2nd place but not pb
Obstacles: Beat my pb (by a landslide)
First ever track: Beat 2nd place but not pb
It is possible: Beat 2nd place but not pb
Snake Pass: Beat 2nd place but not pb
Jumps and Jumps: Beat my pb
Ramps with stripes: Beat my pb
Assuming you are Venca, I beat your time on each track with default settings.