To null the JupiterX version, in the file jupiter/framework/admin/control-panel/logic/fuctions.php, edit the file jupiterx/lib/init.php and in one of the functions that gets called during the init sequence (e.g. the jupiterx_add_theme_support function) add this code:
update_option('artbees_api_key', '123123123123');
The theme will be automatically activated and plugins and demo content can be installed.
I don’t know how long demo content will be installable for – this developer seems to have gone backwards and forwards over the years with requiring an artbees account to access demos. At the moment they install with no problems.