Touching the center selects the leftmost layer vs the rightmost layer under the touch. This creates the potential for the unintentional altering of a non-visible layer. In a complicated watchface this should be disastrous.
Also if a touch is within a layers blue bounding box & outside the visible feature, that layer will be selected provided no layer is beneath.
Bug Demo Link:
https://www.dropbox.com/s/rreygdmimjotdvg/Layer%20Selection%20Bug.watch?dl=0