Cubase 4 and Mac OSC 10.9

howdy… im in same boat. Cubase 4. bought a new MacBook Pro with 10.9.1 on it.
installed c4 no problem and the update from the website… but however my project files won’t load. gives me a error message about not being supported… Weird. its the same program I used to create it on. any suggestions? thanks!
I know its time to upgrade to C7… but… need to get to my files. LOL
thanks
CZ