Custom Spell DC Calculation

[Derequa]

Hi I am new here and relatively new to creating custom pathfinder hero lab content.

I am currently developing a custom Witcher class for Pathfinder, and am creating a hero lab .user file to support it.

A challenge I am facing is altering how hero lab calculates/displays Spell DCs.
The way I have been designing Signs (witcher spells) is such that they are only ever 1 level, but the Signs themselves get stronger as the character levels. Because of this, I want the spell DC displayed on the class's tab and in the spell descriptions to use 10 + 1/2 class level + casting modifier as the calculation for the spell DC instead of the normal calculation.

What would be the best way to implement this? Currently I am trying to use a custom sub-school for all of the signs and bake in an adjustment in the class helper but I haven't gotten anywhere with it yet.

Any help would be appreciated! I absolutely love using hero lab and I hope to get better with modifying it.