Hi, for the first question.
In the dashboard, go to Appearance->Theme Options->Design Options Tab->Custom CSS. Paste the following css and click on ‘Save all Chagnes’.
#access {
border: medium none;
}
For the second question, the menu is placed below the header image. We have designed the theme way. If you use a slider just like in our demo the menu will appear above it. If you want the menu above the header image. It will need coding and corresponding css changes for which you may need to hire a developer.