Yes! Got my SB 1.2.1 from github. I actually cloned latest version and builded it with ./build_distribution.py --version 1.2.1
That was painless, not a single black hole was created. Thanks for the tip, @birkemose!
EDIT: Something is wrong. It doesn't matter which version i'm building. Results are the same.
It shows different versions in "About SpriteBuilder", but file formats are .sb (new version), not .ccb, etc.