#3.1
Then you'd end up with something completely useless. All the libraries
and c: commands and etc., won't work on less than a V39 ROM.
It isn't that C= is trying to force you to buy a ROM. It's that the 3.0
disk set must have the 3.0 ROM to work. They depend on the new system
routines.
—
Dale L. Larson, Intangible Assets Manufacturing