Hi,
as already reported there are failures while loading .mcz.
I launched the debug version from Terminal and got some feedback:
/Users/nicolas/Smalltalk/OpenSmalltalk/opensmalltalk-vm/build.macos64x64/squeak.cog.spur/CocoaDebug.app/Contents/MacOS/Squeak
(lip > (methodField + ((mframeIsBlockActivation(lifp) ? sizeof(CogBlockMethod) : sizeof(CogMethod))))) && (lip < (methodField + ((cogMethod->blockSize)))) 22043
(lip > (methodField + ((mframeIsBlockActivation(lifp) ? sizeof(CogBlockMethod) : sizeof(CogMethod))))) && (lip < (methodField + ((cogMethod->blockSize)))) 23333
Illegal instruction: 4