Awesome spate beck, despite the walk-in! Starting from Black moss pot, (a slot drop with a nasty towback), there's a couple more hard rapids, followed by a long section of grade 2/3. The fairy glen and Galleny Force (~4m drop) make up the lower, very continuous section, with long technical slides and excellent challenging rapids in a gorge.
Drive up the track from Stonethwaite and park at the campsite, then follow the path up as high as you can be bothered, inspecting en route. Get out when you return to the campsite.
Rainchasers is best experienced as an app.