Cubase LE 4 can't be installed on Snow Leopard because some OEM partners have changed the data structure of the original Cubase LE 4 DVD.
- From the OEM DVD copy the folders "Cubase LE 4 for Mac OS X" and "Cubase LE 4 for Windows" to your HD and burn them on a DVD that you call "Cubase LE 4".
- Download the Mac update to Cubase LE 4.1.3
- Now insert the newly burned DVD and click on "Next".
- It is advisable to download and install the latest eLicenser Control Center from http://www.steinberg.net/en/company/technologies/elicenser.html