If you close the window by click close button on the left top corner, it won’t crash.
Here is the info after crash,
Problem Details and System Configuration Process: Corona Simulator [14644] Path: /Applications/CoronaSDK/Corona Simulator.app/Contents/MacOS/Corona Simulator Identifier: com.coronalabs.Corona\_Simulator Version: 2013.2100 (2013.2100) Code Type: X86-64 (Native) Parent Process: launchd [212] Responsible: Corona Simulator [14644] User ID: 501 Date/Time: 2014-02-14 10:42:50.237 +0800 OS Version: Mac OS X 10.9.1 (13B42) Report Version: 11 Anonymous UUID: 896BD456-38B0-A151-3E2D-959575DC6FBC Crashed Thread: 0 Dispatch queue: com.apple.main-thread Exception Type: EXC\_BAD\_ACCESS (SIGSEGV) Exception Codes: KERN\_INVALID\_ADDRESS at 0x0000000000000000 VM Regions Near 0: --\> \_\_TEXT 0000000109ec8000-000000010a0ce000 [2072K] r-x/rwx SM=COW /Applications/CoronaSDK/Corona Simulator.app/Contents/MacOS/Corona Simulator Thread 0 Crashed:: Dispatch queue: com.apple.main-thread 0 com.apple.CoreFoundation 0x00007fff829640af CFDataGetBytePtr + 15 1 com.coronalabs.Corona\_Simulator 0x0000000109edadb3 0x109ec8000 + 77235 2 com.coronalabs.Corona\_Simulator 0x0000000109edae89 0x109ec8000 + 77449 3 com.apple.AppKit 0x00007fff84a98f71 -[NSWindow sendEvent:] + 3721 4 com.apple.AppKit 0x00007fff84a39ca2 -[NSApplication sendEvent:] + 3395 5 com.apple.AppKit 0x00007fff84889a29 -[NSApplication run] + 646 6 com.apple.AppKit 0x00007fff84874803 NSApplicationMain + 940 7 com.coronalabs.Corona\_Simulator 0x0000000109eca274 start + 52 Thread 1: 0 libsystem\_kernel.dylib 0x00007fff87194e6a \_\_workq\_kernreturn + 10 1 libsystem\_pthread.dylib 0x00007fff8cdf6f08 \_pthread\_wqthread + 330 2 libsystem\_pthread.dylib 0x00007fff8cdf9fb9 start\_wqthread + 13 Thread 2:: Dispatch queue: com.apple.libdispatch-manager 0 libsystem\_kernel.dylib 0x00007fff87195662 kevent64 + 10 1 libdispatch.dylib 0x00007fff8d74c43d \_dispatch\_mgr\_invoke + 239 2 libdispatch.dylib 0x00007fff8d74c152 \_dispatch\_mgr\_thread + 52 Thread 3: 0 libsystem\_kernel.dylib 0x00007fff87194e6a \_\_workq\_kernreturn + 10