Fixed background

To make your background image fixed you need to select the container and go to Properties Panel/Background and select Fixed tab.

ScrSht 2015-09-03 at 18.47.49

Fixed Menu

To make a fixed menu like this:

fixed menu

1. First you have to switch to Advanced mode

2. Select the Navigation Widget in Widget Tree

and in Widget Properties Panel/Advanced/Position select FIXED

ScrSht 2015-01-16 at 16.09.06

 

3. In Widget Properties Panel/Advanced/Z-index type in 3. The z-index property specifies the stack order of an element.
ScrSht 2015-01-16 at 16.17.27
An element with greater stack order is always in front of an element with a lower stack order.

Note: z-index only works on positioned elements (position:absolute, position:relative, or position:fixed).