spreadshirt menu – cart

Hello there
my website is http://www.musthave.moda
and i saw your demo website http://lovetee.de/

what i want is
my spread shirt menu to work just the way it works on your website
it only show up on where the spreadshirt clothings ( products are )
see the screen shot http://screencast.com/t/a8uKeex6d

mine is not working at all
i see that i add an item to my cart but when i want to klick
on the top menu of my spreadshirt to go to my checkout page
it dos not work.check it for your self on my website.
mine spreadshirt menu is in the wrong place
see the screenshot http://screencast.com/t/Hq10jOlPo06x
not above the producta like it shows up on your website
mine gos behind the original menu
see the screen shot http://screencast.com/t/M39g2gLb

can some one please help me with this?
do you have a special css script for me so help me with this?

https://wordpress.org/plugins/wp-spreadplugin/