4th ed examples won't build with OSX 10.6 and xcode 3.2


I’m getting errors and warnings that seem to indicate that 4th edition examples are meant for OSX 10.7 and xcode 4, but I’m using OSX 10.6 and Xcode 3.2.

I already edited Project Settings to set Xcode 3.2 but continue to get these errors when I try to build Typing Tutor. I have no idea where to look for fixes. This is my first try; presumably the same types of errors will occur when I try other examples.
How do I fix Xcode settings for all of them? Is there an errata file somewhere, which would include my problems?



Check dependencies

[WARN]Deployment target 10.7 for architecture ‘x86_64’ and variant ‘normal’ is greater than the maximum value 10.6 for the Mac OS X 10.6 SDK.

error: unknown property attribute ‘strong’
@property (strong) NSColor *bgColor;
warning: no ‘assign’, ‘retain’, or ‘copy’ attribute is specified - ‘assign’ is assumed
@property (strong) NSColor *bgColor;
warning: default property attribute ‘assign’ not appropriate for non-gc object
2 warnings and 1 error generated.