Problem with equations in CREO NC

Hello!

In Creo NC Complete (5.0.4.0) when I create a new machine code for NC-machine, equations are automatically substituted.

CUT_FEED = (CUTTER_DIAM/80)*SPINDLE_SPEED*2
SPINDLE_SPEED = 150000/(3.14159*CUTTER_DIAM)
STEP_DEPTH = 0.1*CUTTER_DIAM
CLEAR_DIST = STEP_DEPTH+5

If I set my parameters (for example, SPINDLE_SPEED), they are updated to default anyway.

How can I change or remove these equations?

Please help me solve this problem