I forgot to mention that when I was building my site I later decided to increase the tracking on all the fonts to make it a little more readable. Rather than going back and editing it all in Illustrator I decided to set the tracking to 1 px in Catalyst. You can see the property settings in the screen capture. Maybe that had something to do with it because I don't remember having the problem before that.
I also just noticed that bold is not displaying as bold. It looks just like the rest of the type.
I also noticed that if I select a text box in Catalyst and go to the edit in Illustrator function, it opens in illustrator and looks fine. However when I close the file in Illustrator and save it it give's me an error message saying that some of the font attributes have been dropped. It still looks ok when you are back in Catalyst but maybe that error message has something to do with why it's not appearing correctly after it's been exported and posted online.
I believe the bug you're running into was addressed recently and will be fixed in the final product. If you'd like to post your Catalyst project file I'd be happy to verify that.