AutoCad :: Field Inside Block

We are using both AutoCAD 2013 and AutoCAD LT 2013, and are having some difficulties doing something that seems reasonable...

Basically, we made a block that has the following attributes:

LENGTH
ORDER
CUT-OFF
MATERIAL
CUT-LENGTH
CUT-WEIGHT
CUT-PER-FOOT

When we define this block, we set the value for "CUT-WEIGHT' as (CUT-LENGTH - WEIGHT-PER-FOOT) and "CUT-LENGTH" as (LENGTH - CUT-OFF)

Those formulas work when we initially create the block. The goal is to be able to change the "LENGTH" and "CUT-OFF" attributes, and have the block automatically calculate the CUT-WEIGHT and CUT-LENGTH based on those values.

The issue is that once the block is created, the formulas no longer work. We have tried Update Fields, we have tried REGEN, REGENALL and more, but nothing seems to work. The only thing we have been able to do is define the block, then basically create the block a second time, with those respective attributes being linked to the initial block, which is both not ideal, and created other problems.

I am attaching a copy of one such block, how to make this block work properly.

The final use of this block is to insert it into Shop Drawings for our Companies Products and then link the block to a table that shows the values of the blocks as a Bill of Materials.

I am unable to currently upload a copy of any Shop Drawings, but if need be, I could ask for a "Dummy" Shop Drawing that I could upload.

TAG - TUBE STEEL 4 x 2 x .25.dwg