Hi, Ok targeting a more interesting sample now and I run into a problem where the app crashes when it tries to load the MyDocument.nib file. Any ideas on how to debug what's going wrong? The source is at http://github.com/alloy/macruby_rubycocoa_layer/tree/master Cheers, Eloy Backtrace =============================================================== #0 0x94beb6e4 in objc_msgSend () #1 0x9401070f in -[NSWindowController setWindow:] () #2 0x93f9b5ac in -[NSWindowController _windowDidLoad] () #3 0x93f396f4 in -[NSWindowController window] () #4 0x93f395f4 in -[NSWindowController showWindow:] () #5 0x93f39537 in -[NSDocument showWindows] () #6 0x93f377fd in -[NSDocumentController openUntitledDocumentAndDisplay:error:] () #7 0x93f37348 in -[NSDocumentController(NSInternal) _openUntitled] () #8 0x93f3719a in -[NSApplication _doOpenUntitled] () #9 0x93f3687c in -[NSApplication(NSAppleEventHandling) _handleAEOpen:] () #10 0x93f360a3 in -[NSApplication(NSAppleEventHandling) _handleCoreEvent:withReplyEvent:] () #11 0x96dda1df in -[NSAppleEventManager dispatchRawAppleEvent:withRawReply:handlerRefCon:] () #12 0x96dd9eef in _NSAppleEventManagerGenericHandler () #13 0x9057d648 in aeDispatchAppleEvent () #14 0x9057d57e in dispatchEventAndSendReply () #15 0x9057d425 in aeProcessAppleEvent () #16 0x957bcf61 in AEProcessAppleEvent () #17 0x93f339ed in _DPSNextEvent () #18 0x93f3308e in -[NSApplication nextEventMatchingMask:untilDate:inMode:dequeue:] () #19 0x93f2c0c5 in -[NSApplication run] () #20 0x93ef930a in NSApplicationMain () #21 0x9035d1dd in .LCFI1 () #22 0x9035d771 in ffi_call () #23 0x002a1080 in bs_function_dispatch (argc=2, argv=0x40050, recv=16896800) at objc.m:1530 #24 0x00286fa5 in call_cfunc (func=0x2a0e00 <bs_function_dispatch>, recv=16896800, len=<value temporarily unavailable, due to optimizations>, argc=2, argv=0x40050) at vm_insnhelper.c:280 #25 0x002946c0 in vm_call_method (th=0x10143a0, cfp=0xbff88, num=2, blockptr=0x1, flag=2145, id=10149, mn=0x1593fa0, recv=16896800, klass=16896832) at vm_insnhelper.c:370 #26 0x0028e618 in vm_eval (th=0x10143a0, initial=0) at insns.def:1085 #27 0x00293b6c in vm_eval_body (th=0x10143a0) at vm.c:1153 #28 0x00293e41 in rb_iseq_eval (iseqval=17559888) at vm.c:1362 #29 0x001d2dfa in ruby_exec_node (n=0x10bedb0, file=0x10bc091 "/Users/ eloy/Documents/DEVELOPMENT/RubyCocoa/src/MacRuby/rubycocoa_layer/ MiniBrowser/build/Release/MiniBrowser.app/Contents/Resources/ rb_main.rb") at eval.c:237 #30 0x001d87af in ruby_run_node (n=0x10bedb0) at eval.c:265 #31 0x0029ec2b in macruby_main (path=0x1ff4 "rb_main.rb", argc=3, argv=0x40a660) at objc.m:2453 #32 0x00001ff2 in main ()