How to find the uname of a shape?

[abssorb]

I searched and found a trick to get the uname of a page....
http://visguy.com/vgforum/index.php?topic=3898.msg15190#msg15190

=BKPAGENAME(750)

Is there an equivalent trick to find the uname of a shape?   I'm trying to make a master, and refer some text to a rectangle, but this is driving me crazy. 

If I create a brand new clean file and make a master as an experiment, and use this formula for PinX - it works perfectly:
=Rectangle!PinX-Rectangle!Width*0.5+1.2

However if I try and do it on the sheet I'm trying to modify (inherited), then editing the master - I can see the name of the rectangle is:
filename:Stencil:Person:Rectangle

But when I modify the text's PinX to be =Rectangle!PinX-Rectangle!Width*0.5+1.2
All I get is: "Error in formula"

I do with Visio would be more verbose with its errors.  I don't really know why this is happening, but name / uname is something I'd like to eliminate

[Surrogate]

Code

NAME(750)

Read more about this function https://documentation.help/MS-Office-ShapeSheet/DSS_Functions_%28M-P%29_1580.htm

[wapperdude]

VisioGuy did an article on ways to get shape name info:  http://www.visguy.com/2009/07/15/whats-my-shapes-id/