I'm a novice Pod X3 Live user, but I had similar problems with L6 Monkey 1.68 crashing some months ago under OS X Mavericks I found reverting to Monkey 1.65 worked in OS X Mavericks and it is still working in OS X Yosemite 10.10.1. Gearbox 3.72 also works in Yosemite. You can find Monkey 1.65 here (http://line6.com/software/index.html), but you need to search for "All products": "Line 6 Monkey": "Mac OS" first and the then tick the "Archived" Button to find it. I have not tried Monkey 1.66 or 1.67, but 1.65 works in Yosemite. I expect you'll need to Google how to fully remove 1.68 first before re-installing 1.65. Real shame Line6 are alienating existing customers. Like others here I'm sticking with the X3 Live because of its Bass support, but won't be buying L6 again unless they buck up their customer support.