// asked the Mods to clean up this mess … rowie, PLEAZZE don't post same Q THREE times!! //
3 remarks from here:
• roots of your problem is, I guess, you followed Fox' advice in your other thread, setting a starting point, which asks for converting a Shape to points … read my first reply in that thread: no need to convert! Starting-point of the Shape is upper-left, I marked it with a 1.
no conversion = width available 😉
• there's a simple, cheesy trick: link the SCALE/x-axis of the group containing your converted-to-points rectangle to width of text …
yeah, before Fox collapses - this is not Lege Artis, it will adjust the 'thickness' of the vertical lines too … but, depending on what factors are in use, … red-arrows-time:

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rectangle converted to points, groups X-scale linked to text width, gives…

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… automatic resizing! But …

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… on excessive increase, the width of vertical line gets affected …
• actually, you can link 'somehow' Points to Width, but this asks for some really tricky/lengthy workaround, using nil-objects, the Track Points Behavior etc etc … see pt#1= goto the roots of your 'problem', no need for tricks …in your case.