SCAL had to stop working with the Cricut machines because of law suits.
SCAL2 is the last software edition that worked, but only if you didn't update your firmware on the Cricut itself.
I found this list of firmware versions on a chat board. These are the latest that will work with SCAL2.
"If you're happily using SCAL then there is no need to update your Cricut firmware beyond the versions listed below. Keep in mind these are the highest...