The test website can be found here: http://test.magichost.ro/prestashop/ Those boxes in the middle of the page look ok in IE8, Firefox and Opera, but in Chrome and Safari they jump below one another. I looked with Firebug for Chrome at the code and it says it only loads the first <li>, so just the first box. No idea why.
Unfortunately you have it all backwards. IE is wrong and all the other browsers show it correctly. Firefox and Safari are 99.9% correct in terms of how they display the page. You need to recode your website so that it appears correctly in Firefox by default, and then worry about making IE work.
I believe you didn't stop to fully read what i wrote there. Works in IE8, Firefox, Opera. Doesn't work in Chrome, Safari.