Basic-boy question about Mod Spell Magnitude on Ability Constant Effect

[abborre]

As part of a wacky system I'm trying to cobble together, I ran into this hiccup.

 

I've got a Perk that adds an Ability, and the Ability has a Constant Value Modifier effect that modifies a custom actor value.

The Perk also contains a Mod Spell Magnitude entry, that is supposed to help govern the magnitude of the Magic Effect in the aforementioned Ability, cuz reasons. Only, I can't get it to affect the amount of the actor value that gets modified by the Magic Effect. I just get the base magnitude, even if I try to modify it with an entry from another perk.

 

Is there some really basic principle that I somehow haven't understood? Can Ability Magic Effects not be modded like I want them to, is there something wrong with the flags somewhere?

 

The Ability Spell:

• Flags: Manual Cost Calc, Are Effect Ignores LOS (the ability also handles cloak effects)
• Type: Ability
• Cast Type: Constant Effect
• Target: Self

 

The Magic Effect:

• Flags: Recover, No Duration, No Area
• Archetype: Value Modifier
• Casting Type: Constant Effect
• Delivery: Self