Today I rode the Juvie again and confronted my failings from the first trip.
In a nutshell it was good. I coped with most of the “difficult” stuff far more easily, and even managed the boardwalk 4 times out of 4 (last time I messed it up 3 times out of 3). The corner that follows the boardwalk I find really tricky, but I managed to get around it perfectly once.
I gave the slalom a go too, it went well until time 3rd time, when the back wheel detached during a moment of over-hard braking. A kind fellow rode over to help me diagnose and fix the issue. He said he had seen front wheels detach but never a back wheel!
Anyhow, I went around again without much incident and was pretty happy with how it went.