mobile menu

Dear,

Even after updating to 1.4.2 Highend still some problems with the mobile menu. On my iPhone the last item in the mobile menu is still not showing.
Furthermore, I’m also still looking for a way to have the Menu button vertically centered both before and during scrolling (pic included)

Currently I’m already using this css for the menu on mobiles:

@media handheld,only screen and (max-width:900px){
#logo { width:80% !important; }
#show-nav-menu { line-height:50px !important; }

I’d like to find a solution to both problems. Thanks.