Trying to run web content from the file system is never a good idea; as you're discovering, most browsers' local security protocols will block a lot of the functionality.
There are ways around this but they differ from browser to browser and it's always difficult to be sure whether the settings you have applied work or not - far easier just to run the course from a web server.
As Helen points out, that's why there's a preview function built into the authoring tool.
If you do need to use something else then you could try:
If you're running Windows you could enable the IIS feature of Windows; if you're running macOS has Apache pre-installed, it's just that finding it and switching it on is not as easy as it used to be.