Vuforia causes lag in editor?

My AR project, which runs at a solid 30 fps on my five-year-old iPad 2, has a huge hang time when enabling or disabling the QCAR Behavior (with all the AR functionality) in Vuforia. The whole app freezes for 10 seconds or so in the editor. This lag does not occur as badly on the device, but it's still there. After it happens the framerate is fine -- but is there any way to deal with this hang time? Has anyone else experienced it, or worked around it in their apps? Any help would be appreciated! I'm using the latest Unity 4.6, and the latest Vuforia AR plugin, downloaded yesterday. I'm running the editor on a macbook air, though my friend with a macbook pro experiences it as well. Anybody else getting this?