note: Your exampe doesn't include an HTML element with the ID of stats, I will assume that this element actually exists within the generated page.
There are a number of issues with your example:
1. You are trying to reference the HTML element with an ID of stats-will as if it was a variable.
This won't work, and doing so is unecessary because that element is just displaying the current value of your $pcWill story variable, which is what you should be referencing within the conditional expressions of your <<if>> related macros.
2. The syntax of your multi-part conditional expessions are invalid.
3. The conditional expression of your third <<elseif>> macro contains an or operator instead of an and.
Try replacing the <<if>> related macros with the following.
<<if $pcWill gt 0 and $pcWill lte 5>>
<<replace "#ccwillfeedback">>//Broken//<</replace>>
<<elseif $pcWill gt 5 and $pcWill lte 10>>
<<replace "#ccwillfeedback">>//Focused//<</replace>>
<<elseif $pcWill gt 10 and $pcWill lte 15>>
<<replace "#ccwillfeedback">>//Resolved//<</replace>>
<<elseif $pcWill gt 15 and $pcWill lte 20>>
<<replace "#ccwillfeedback">>//Tenacious//<</replace>>
<<else>>
I cannot properly assess this yet.
<</if>>
warning: The above example has not been tested.