You MUST install this version for it to work correctly.
See share/core.js for the (Platform) Native interface.
GHTML requires the -f FILENAME switch to load HTML docs. If you did not perform installation, JSE will not be available in GHTML. Otherwise, you have a JavaScript/C programming environment with GUI!
There are bugs and some missing features, which are yet to be determined, or already documented somewhere in the code-base.
If you need help, don't hesitate to shout at the issues page.
Happy Coding!