I'm afraid that this documentation is specific for AWS cloud images, which slightly differ from the instructions required for the OS X VM.
Once the VM is started using the graphical interface manager (see this for an example, you can click on the
Volumes tab, and mount the
/opt/bitnami volume. Then clicking on
Explore will open this directory in the Finder. You can then navigate and inspect/edit files, letting you open the conf. file using your favorite editor.
Would this work for you?
Also, just wanted to let you know that I've forwarded this case to our documentation team so the instructions for this use case are improved.