Appearance Mode Slider Previews are Broken

I was trying to modify a shape last night and found that most of the little preview graphics in Appearance mode did not show any difference at either extreme of the slider values. This made modifying my shape incredibly hard as all I had to go by was the name of the slider. (I eventually gave up.)

I have confirmed this is a problem on three different computers under two different accounts, so I don't believe it's anything related to just me. The odd thing is SOME previews still work (all of the body sliders do, and the "head size" slider preview is the only Head slider one that works.

Here are some examples:

The 'head size' preview correctly shows small and large head values, but the subsequent slider previews show no change in either direction.



The Eyes slider previews are all identical to each other except for Eye Spacing, which freakily moves my eyeballs but not the eye sockets.



The Body slider previews all look fine.



It appears that anything related to the head (Head, Eyes, Ears, Nose, Mouth) is basically broken except for 'Head Size.' Anyone else seeing this?