Flash CS6 Symbol Placement Limitation

I have Adobe Flash Pro CS6, and I'm having a problem placing a graphic symbol on the right side of the stage.  It tweens from being large in the center to being small on the right side of the stage. The tween works perfectly (slides and shrinks like it's supposed to) right up to the ending keyframe, then it moves left inside the symbol box. I've never encountered this problem before, and I can't even figure out how to look it up.

The first keyframe has the larger image symbol in the center of the stage. Then I place another keyframe on the timeline where I want the tween to end. Then I resize the symbol to the smaller size. Then, when I try to slide the symbol to the point on the stage where I want it to end up, it's like the image hits some kind edge and stops. It's still well inside the actual edge of the stage, and a number of other symbols work perfectly fine past that point. It also works if I leave the symbol large and slide it around with the mouse, but if it's small, it won't work. I can actually see the image "hit" some kind of right edge as I move it with the mouse. The bounding box will continue past that point, but it's like the image slides right out of it stuck on a right-side limitation that shouldn't exist.

I know I'm over-explaining this, but it's driving me crazy. It should be a very simple tween with no problems.