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.