You don’t need an install.php
1.8 uses a completely different structure to 1.7. If you’re doing a fresh install there’s no need to go to 1.7.6 first. You can fresh install 1.8.0a3 but remember it’s an alpha so it’s not supposed to be used for production.
You should make the web directory your web root and not expose the folders below that. It should work with PHP 7.0.5 but it’s not something we’ve actively tested yet. You’ll also need to get the PHP zmq extension installed for 7.0.5 (if it exists as a binary) if you want to use XMR.
You could be better off waiting for us to release the instructions for running Xibo 1.8 under Docker on Windows. Then all this is taken care of for you.