yes, please run the command I posted before installing rockpool, or for that matter anything. Until the filesystem is expanded there will be very little room, and you will run into trouble pretty much right away - this has nothing to do with Rockpool per se, but the way imaging Jessie works.
Alternatively run:
curl -sS get.pimoroni.com/rockpool | bashwhich should also prompt you to expand the filesystem to use up the entire SD capacity if there is not enough space for the estimated requirements.