Is this a Yosemite thing? Has anyone else experienced this? If you fixed it, what did you do? Is there a bit of the error log that I can copy and paste in here to help diagnose? Is this just going to get fixed in the next few days?
I'm not 100% sure it's caused by Yosemite because I hadn't used ADE for many weeks prior to the update, but it's the only major thing I can think of that's changed.
In the mean time, is there any other program that can open .acsm files on a Mac running Yosemite?