symbolic evaluation in prime 11.0.1.0

I am not sure what the problem was, but I see when I load your file that you experienced a “variable not defined” error.

But when I simply let your sheet recalculate (Ctrl+F5) the symbolic evaluations work as expected:

The two substitutions are not taken into account because you used the Boolean comparison operator instead of an assignment/definition.
If you use the assignment operator, you will receive error messages, but these come from the numerical engine in Prime; the symbolic evaluation, however, works as expected.

Or perhaps you actually intended to use the assignment operator in the symbolic evaluation as well? Also For example Iwp := 2*… .