Did this get resolved? I'm still in a holding pattern.
Ok, here's a new build of the Eventide Direct Updater that should fix the problem with it not launching on some Yosemite computers:
This new build fixed the problem on my colleague's Yosemite machine, and it should fix the problem for all of you as well. Please try it out and let me know if it fixes the problem for you. If it does, we'll replace the builds on the Support / Download page with the new version.