Hi, for anyone interested to run Rockpool and Flotilla on a pi-top (which is at the moment raspbian wheezy based) you have to change the port that Rockpool binds to (it defaults to 8000 that is already used by node-webkit on the pitop for its custom “dashboard”).
you can do it easily editing the port in rockpool.py choosing one that’s not already used.
You can check already used ports by issuing this command:
sudo netstat -plunt
In my case I’ve used port 8001.
edit: better use sudo before netstat