Problem with setting effect properties that are Expression Controllers

[wmwccdd]

My template has a few things controlled by some expression controllers like sliders and checkboxes. So for a simple example, lets say I have a layer called CTRL and there is a slider control named BoxWidth that drives the width of a shape layer rectangle. I'm trying to pass a value to that slider using this:

"assets": [
{
"type": "data",
"layerName": "CTRL",
"property": "Effect.BoxWidth.Slider",
"value": 1
},
]

I would get this error:
Can't find a property sequence BoxWidth.Slider for key: BoxWidthwithin layer: CTRL

The idea being that I have several other things connected to the box width, and I'm trying to keep driving them with this one slider. Any thoughts would be appreciated!

[wmwccdd]

Actually got this working today by renaming the layer to Controller instead of CTRL. Not sure why that did the trick but it did.

[tolgaburcak]

Try Effects instead of Effect
"property": "Effects.BoxWidth.Slider",

[wmwccdd]

Yeah sorry my post here contained a typo. The actual JSON said Effects. The only thing that fixed this issue, for some weird reason was to rename the layer Controller instead of CTRL.