Curves/Picker doesn't work on Affinity Photo 2

[TVIL]

I don't know if I'm using Picker correctly, but when I activate it, Picker doesn't work. According to this tutorial, Picker “blocks” color tones: 

 

[HCl]

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[TVIL]

Ok but I want to do the same thing as on the Youtube tutorial video:

 

[HCl]

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[TVIL]

[HCl]

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[TVIL]

Had I known that this problem had been reported, I wouldn't have asked the question in the forum.

[HCl]

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[TVIL]

3 hours ago, Return said:

but moves/drags the picker sideways as opposed to up down which adjusts the curve.

In terms of use, it's not very intuitive or precise, because all it takes is one “wrong” movement and the curve is moved. Clicking on the image to create a node on the curve seems to me to be more effective.

[HCl]

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