I've not done anything special here, just wrapped the community edition of ISOFLOW https://github.com/markmanx/isoflow
and made it dead easy to set up and run.
You can now export and load JSON backups of your diagrams allowing you to essentially have as many as you want, which the community version of ISOFLOW restricts. Enjoy!
I'm not very familiar with Node.js. Any idea where in isoflow's code are the graphics for those 3D-style icons? Are they SVG or what? Is it possible to add custom icons?