Yasu download url is broken, and without shasum check, it is not caught until installation. The developer has decided to stop maintaining Yasu and has released the last working version various OS X versions, but not supporting the software. This has been noted in the Caveats for user awareness. Added the zap stanza to cleanup cruft left behind.
Yasu — short for “Yet another system utility” — an Apple OS X maintenance utility developed to do a certain group of tasks quickly with just a few clicks, instead of typing a bunch of complex commands in the Terminal application.