ImageElements don't have a control handle, as they aren't controls. Plus! Live itself draws the figures and images using the Windows GDI before the controls get drawn.
However, there's a simple work-around. Create a 1 pixel by 1 pixel PNG image which is empty (i.e.: the only pixel is a fully transparent one) and name it "none.png" or something. Then, use ImageElmt_SetImageFile to set the ImageElement's image to that image. This way, it will draw nothing visible.
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