Look at the browser console
If your map is not displayed correctly (most notably if you are getting a black screen), open your browser console. This is usually done by pressing the F12 key and selecting the "console" tab.
Scan the output. Towards the end, you might see a message explaining why your map cannot be loaded.
Check webserver CORS settings
If your are hosting the map you built on your own webserver and if the map does not load, please check that your webserver CORS settings are correctly configured.
Need some help?
WorkAdventure is a young project and much needs to be said / written regarding map editing.
If you are facing any troubles, do not hesitate to open an "issue" in the GitHub WorkAdventure account.