The dependent parameters system (using "valueOpKey" statements) sometimes has that problem. It won't reset to zero or won't start at zero.

Try using the older valueOpAdd system, generally known as ERC.

Assuming your prop is called LightSwitch, and it includes a master parameter dial called LightsOn. You want the illumination of the Light to be 1 (or 100%) when the master parameter dial is set to 1,

Here's the code that would go inside the Intensity parameter of the light itself:

valueOpDeltaAdd
    _NO_FIG_ 
    LightSwitch
    LightsOn
   deltaAddDelta 1.0


```The 1.0 is a proportion, which in this case is 1 because the parameter dial and the Intensity both go to 1.
If you wanted the Intensity to max out at 0.4, the deltaAddDelta would be 0.4.

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