Changing Damage Dice for Weapon of Detection (not dam modifier)

I used Charactermancer and I imported a Weapon of Detection onto my character sheet from the compendium. Because my dagger is going to be my weapon of detection, I tried to change the damage from D6 (default) to D4. The D6 appears to be fixed. Is there a way to change the D6 to a D4 on the Weapon of Detection? I know I can just import a regular dagger and change the name, but I lose the magical ability description if I do it that way.

Hi John B.,  Which Character Sheet are you using? If you don't know the name please supply a screenshot. 

D&D 5e

Could you screenshot where you are trying to make the change?