Flexible header and e-mail

Dear support team,

First of all, I’m really satisfied with the Enfold theme. It is the first website I ever build, and it is turning into a success thanks to the user friendly enfold design. However, I cannot manage to make the small fixed header I used fixed when scrolling down. I tried the following code:
#header_main .container, .main_menu ul:first-child > li > a {
height: 88px !important;
line-height: 88px !important;
}
However, nothing changes.
Also, e-mails do not reach my adress neither are confirmation e-mails send. I used an e-mail adress registered by the host ( (Email address hidden if logged out) ) but it doesn’t work.

The adress is http://www.wiconsult.nl

Hope you can help me…thanks already,

best regards,

Gijs