Repro Steps:

1) Create a Page
2) Introduce any visible element to the Page within the RootGrid.
3) Select the newly-introduced object on the Stage or within the Navigator.
4) Select the Selection Tool or the Move Tool, and hover the mouse over the corners of the object's bounding box on the Stage. An arrow icon should appear.
5) With the 'scale' icon is visible, hold [Shift], then click-and-drag the mouse in any direction.

Observe how the proportions of the object are conserved.

6) Release the [Shift] key, and drag the corner of the object's bounding box in any direction.

Observe how the proportions of the object are now freed.

7) With the object still selected, activate the Transform Tool (Y), and hover the mouse over the corners of the object's bounding box on the Stage. An arrow icon should appear.
8) With the 'scale' icon is visible, hold [Shift], then click-and-drag the mouse in any direction.

Observe how the scale of the object is not constrained to the aspect ratio.

Expected Results: Holding the [Shift] key when scaling an object in any mode always enforces a constraining to the aspect ratio of the object before it was clicked-and-dragged to scale.