Scott,
There are several options in the Rendering tab of each object that you'll need to adjust. The behavior you're seeing is occurring because a Layer Object's default Depth Sorting mode for Rendering is Manual, which renders objects towards the bottom of the Object Manager in front of objects towards the top. So a child of a text object, which is necessarily below the text in the Object Manager, gets rendered in front of it.
You can change the Depth Sorting mode in the Layer Object's Rendering tab to Automatic, but you'll have to make some other adjustments to your objects at that point, depending on how complex your scene is.
When I tested a simple scene as you described, once I set the Layer Object to Automatic Rendering, I had to either (a) check the option on the the masks's Rendering tab to "Render on Top" OR (b) change the Text's Render Order Priority from Text on Top to Normal, so it would get hidden by the mask, then set the Z Position of the Quad to -1 so it would appear behind the text.
I should also add, it's probably easier to accomplish what you're looking to do using Visual Logic, rather than Auto Scale. You can tie either the width or the Scale.X of the quad to the BoundingBox.Width of the Text Object, then you don't need to worry about having the Quad be a child of the text object, nor changing your render settings for your Layer Object.
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Jeff Mayer
Ross Video
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