Ok, better late than never...
I downloaded the new version of MBM5 and did and update to my existing installation and had the same issue. I then had the thought that it might be better to do a full install than an update. (After seeing first hand how much trouble creating installs can be) So I uninstalled my existing installation of MBM5 and tried installing a fresh copy. Once I rebooted I gave it a try (a few times) and kept getting a message that it couldn't install the new MBMIO driver. The fix for this is to log in as the local admin. Even though I was logged in as a user that had administrator rights, apparently this was different than being logged in as the "real" machine admin.
Bottom line... I'm now getting temps again consistently.