iPhone simulator error

Hi there. I'm developing using a Mac and newest SDK:

Host OS: Mac OS X
OS Version: 10.9.1
OS Arch: x86
Titanium Studio Version: 3.2.0.201312191547
Latest Titanium SDK: 3.2.0.GA
Android SDK Version: 4.4
Titanium CLI Enabled: true
Node.JS Version: v0.10.13

Today I was working for about 2 hours when at the nth run, using iOS simulator, the app didn't start anymore! I didn't change absolutely nothing! Oh well, I changed 1 or 2 code lines since the last working run but it isn't that: I re-changed them and nothing changed.

And from then on, that app didn't work anymore. It works without any problem on Android emulator (I use BlueStaks) or on Andoird device, but not on the iOS simulator anymore.

If I run it, it compiles, then the simulator opens on the home screen (the one with Safari at the bottom) but nothing more happens: no more "red Appcelerator" screen. And in the console I read:

...
[INFO] :   Alloy compiler completed successfully
[INFO] :   Initiating Xcode pre-compile phase
[INFO] :   Processing JavaScript files
[INFO] :   Skipping xcodebuild
[INFO] :   Finished building the application in 2s 983ms
[INFO] :   Running application in iOS Simulator
[INFO] :   Launching application in iOS Simulator
[INFO] :   Focusing the iOS Simulator
[ERROR] :  Project failed to build after 1m 33s 425ms

I tried to empty the /Library/Application Support/iPhone Simulator/ folder.

I tried the "iOS Simulator -> Reset content and settings" on the simulator itself.

Obviously, I restarted Titanium and the Mac ... but nothing changed.

Could you help me? Thank you in advance!