I did a fresh install of the new vuforia stuff in a new project using unity 4.1.5f1
I imported the imagetarget scene, the userdefined target example, and the multitarget examples.
That threw an error with the userdefinedtracking handlder scrip at this line:
return new UIButton(rect, newUDTButtonStyles, imageForButton);
and the error said UIButton doesn't take 3 parameters. Commenting it out gave a few more errors.
Then on the imagetarget scene, simply opening it after installing, it throws a nullrefexception on start, in regards to this line in AppManager.cs: