WinXP IE7 and Firefox seem to load your page fine. WinXP Safari seems a bit sluggish to load and render, and eventually slow-loads your logo image blown-up as a background image (revealing the "If you can read this..." message on the left). My colleague with a MacBook is preoccupied at the moment, but I can have him test your page once he's free; however, our cart is normally perfectly compatible with Mac browsers.
Taking a look at your page's HTML source, I noticed you seem to have many duplicates of our View Cart button code, not just for visible View Cart buttons but also leftover pieces of that code that were apparently left behind when the button image/link itself was deleted. The View Cart code is specific to your cart but the same for all your products, so you only need to paste it in your page once, as it contains extra tags to load the script resources from our server that make the cart work. There's no need to load those scripts more than once on a page, and having more than one set of View Cart code in a single page can slow things down, but deleting the visible button image/link does not delete those extra script tags. See what happens if you remove all the View Cart button code (or buttonless orphaned code remnants :^) you can find in your page's HTML source, then paste just one block of View Cart code back into the page.
