I have made a new release 0.22.0 that finally fixes the issues we were having with the binary release of the Mac stand alone. It turns out that when you run the code using gradle, it has already loaded all files into memory, so accessing the files is fast enough to be done in a UI thread, even though this is discouraged. In the Jar form, the timing overran, and Mac UI managed froze the program. I have now made (further) sure that file access takes place in a normal system thread, and UI access is managed by a tiny Platform.runlater code snippet.  This took months to fix because the way Mac breaks is totally opaque to the user and developer. It just hangs, no errors, no exceptions. 

I really hate macs...

Anyway, i also added High DPI screen support by making the font of the text window changeable. Ok, in fairness, all the UI text is still tiny, but the editor is nice and readable.  This will also help with projecting code on a projector for teaching.