Pricing rule: price is not decreased after removed the element

Hello,

I want to apply a pricing rule based on the current size of the added image. The price will change when the customer changing the image size. 

At first, I use "Image size scaled" for "All images", but it will calculate all the default image for background, etc.. and the price is not correct.

That why I added rule "Image size scaled"  for each specific image (I hope we can add kind of exclude element so we don't have to do this). It works, the price is added when I add the element, the price changed when I changed the size. But when I remove the image, the price is the same. 

When I do something to change the price, only at that time, the price is re-calculated.

Can you help me on that?