Did you try more than one project?
Yeah, I think it was the LHC@Home that taxed the computer most. Maybe I could try again by removing that one. But having my computer lock up on me is not a good thing, so it's probably best not to try on this computer.
Did you try without Virtual Box?
Not sure how to do that as I thought the the work units are packaged as virtual box units?
1.5%
If I started as a researcher and now my magnitude is 0, I'm kind of stuck, right? Would I have to somehow set up a different wallet and send my gridcoin there to just do the staking only?
There seems to be more people noticing this very issue with other programs on Mac, Excessive Wakeups @ Official Mac Forum.
Regarding Virtual Box, it's a selection of with or without Virtual Box for the Windows Boinc client at http://boinc.berkeley.edu/download_all.php. But it doesn't seem to be for Mac.
Regarding the 0 Magnitude issue. You can edit the configuration file and comment out the path to the BOINC software. This will make the client change to Investor Mode and you will not have any issues with staking pur interest blocks instead.