Can not set property of Material during runtime

I have defined property of type cc.Integer to get blur value through editor, so that i can customize the blur intensity.I am trying to set property of material during on load like this.material.setProperty("num", value).
num is the property inside effect script(custom effect).But problem is num property is not changing during runtime.
This is custom effect file code

CCEffect %{
  - passes:
    - vert: vs
      frag: fs
        - blend: true
        cullMode: none
        texture: {value: white }
        num: { value: 0.02 }

If i try to give direct value like this.material.setProperty("num",0.01),this woks fine.
cocos version:2.4.6
Thank you

I can ask engineering to have a look.

I have try to setProperty ,and it works well like:

here is my demo: (1.2 MB)