Is that bug back again?
It is not a bug in Armory itself, but in the Qt toolkit that Armory is built upon - not that that helps you, of course. Last time it appeared was when Apple updated OS X, it took ages before the Qt toolkit (or OS X) was fixed.
The bad news is that there is probably not anything the Armory developers can do about it - unless they have learned a few magic tricks since last time, which of course is entirely possible.
The good news is that there is a slightly inconvenient workaround. You only need to backup your Armory wallet once, ever. So you can manually copy the codes from the sheet to be printed to a piece of paper. I have moved a wallet from one offline computer to another in this way once, it did not take long. Of course you need to test your backup extra carefully in that case, but you should always do that anyway, and Armory makes that easy. And you don't need to worry about your printer caching the private keys
That being said, it is a weak point for Armory that OS X support is only given low priority by the developers of the QT toolkit. But there is next to nothing they can do about it.
EDIT for the developers: I am still running OS X 10.9.5. And Armory 0.92.3-beta. That combination works flawlessly.