Thank you for contacting JustAnswer.com with your question. My name is ***** ***** I will be happy to assist you. I understand you are trying to run Google Earth on your MacBook Pro, but Google Earth is crashing after you have imported a large kmz file.
I found a solution to a similar problem on Windows, and I have tailored it to Mac OS X. Hopefully it will work for you in this case. The solution is below:
"Was GE previously installed? If it was, it is possible that your 'Places' file has become corrupted or is somehow interfering with GE. Try this:-Locate your Places file, which is myplaces.kml. You'll find it in:
~/Library/Application Support/Google Earth- When you get to the folder, right-click>rename the existing "myplaces.kml" to "old-myplaces.kml". You should also see a file there called "myplaces.kml.backup", which was the next to the last places file. If you have placemarks from a prior version that you want to try to recover, at that point rename the file "myplaces.kml.backup" to "myplaces.kml", then launch GE.- If you still have the problem, go back to the folder above and delete that "myplaces.kml" file. Then try GE again. If it launches, it should appear with a new Places panel with just a sightseeing tour in it. If you want to try again to retrieve some of your former placemarks, you can then try opening old-myplaces.kml using GE's File>Open menu. If it opens, drag the items you want from Temporary Places to Places."
Please let me know if this worked for you.