(Almost) One Page Website & CSS ID

Need some help with an (almost) one page website I’m creating. Heres the link:

https://goo.gl/4EHm4s

First Issue
I’ve setup the main NAV to scroll to the correct sections using CSS ID, however I have a separate page for the menu which when clicked is impossible to navigate back to the home page as the NAV menu can’t find the CSS ID, how do I resolve this, do I have to setup a separte NAV for the menu page or is there another way?

Second Issue
The scrolling behavior seems to differ, for example if you click on Order is scroll through the page, if you click on Book a Table is just jump directly to that section, the settings seem the same, or am I doing something wrong?

Also it would be great to control the scroll settings and slow down the scroll, is this possible?

Thanks in advance.

The page I need help with: [log in to see the link]