Hi There,
Not sure if this helps you, but I had a similar issue on macOS Mojave after install. In a nutshell, I had a couple of permissions issues.
First, I had to fix permissions on the “/Users/[username]/Library/Application Support/Local/run/router/nginx/logs” folder. Not having write access was preventing nginx from starting (I saw this error in the local lightning log file).
Second, once I fixed the above issue and I got the site to start/load, I was having weird issues updating pages. I use Divi for development and when I would try and update a page it would launch a separate “preview” tab (and not save the changes). I fixed this by fixing the permission on the “/Users/[username]/Library/Application Support/Local/run/router/nginx/client_body_temp/” folder. For this second permission update, I had to use terminal/sudo-commands to fix the permissions.
Both log files (the router log and the main lightning log) were really helpful in tracking these down. I hope this helps.