It’s both the environment you are running and the configuration what need to be set.
I would suggest to test VM with Ubuntu 16.04 server (default installation options), open port 443 to that instance and run the installation script.
Follow the steps and you’ll end with collabora working, because it’s a standard controlled environment.
Take your time to grasp the way it works, check there what you need to modify on your own environment to get it working.
Also you could try the IRC Channel, since it’s a faster way to get in touch with people in real time.
And remember to have fun.