Upon upgrading, we also experienced multiple broken sites as well and the only thing we can identify as a possible cause is that the update requires php v5.4 and our servers have php v5.3.8
If that is the cause, then it would be good if the update notified users about the php 5.4 requirement before upgrading to prevent broken sites and false support tickets about the plugin being broken.
We are staying at the lower version for now.
Best of luck.
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