Vertical bar won't appear and theme settings are wrong when installing Sider

It doesn't seem like the header is being rendered at all on the page. Do you know what could be causing this? I changed my website to my home page from the default blog page and it doesnt even shift the body 300px like it says in the css

Copying the additional CSS from the Site Library seems to have made the menu appear, but the items seem to be in the wrong order now. Not sure what could be causing that.

Looks like you are missing this CSS stil:

.nav-float-right .inside-header .main-navigation {
    order: 2;
    float: none;
    margin-top: 30px;
    margin-bottom: 50px;
}