Excel using vlookup not calculating after 3 steps in spreadsheet---#NAs start "pop up"

Hello,

This is not an issue with formulas not working, but with data entry.

Looking at the formula in Sheet "Computations", cell B8. Unravelling the formula, it turns out that the value "3X" is being looked up with VLookup in a table that shows "3X" as a lookup value, but the actual content of the cell is just a number 3 that has been formatted with a custom format to appear as "3X". 

The value ultimately comes from your Input form, where the value "3X" has been entered into cell B7.

The cell is formatted to show numbers with an "X" following, so the "X" does not need to be typed into this cell.  If you simply type the number 3 into this cell, it will still appear as "3X" because of the formatting and all the follow-on formulas will calculate correctly.

Let me know if that helps.