apportable/SpriteBuilder — pull request #285 by NickyWeber (2014-02-26 21:20:52+00:00)
Title: Fixed issue #253: Project Settings option causes the app to crash when no .ccb is opened.

In AppDelegate.m -updatePositionScaleFactor depended on currentDocument being set but that is not the case after opening a project so it tried to set different scale factors with a value of 0 causing the crash due to assertions. This method is invoked anyways when a document is opened/selected so the guard statement causes no harm.