Help with Landing page

Gday peeps i need a hand with my landing page its all set up ready to go but i have a few issues with the slider image shinking sumtimes.. automaticly i have no idea why this is happening.. and i would like to know how to add a paypal link that gives the option to download once paypal has recived payment..
i cant pay cash but i can do do reviews of products or sum opencart / graphics work within my skill set.. if needed.. cheers n beers.. pls pm me