The mask function "clip next module" looks weird in the preview, but works on the homescreen. I think what's happening is that it no longer zooms with the rest of the widget, it has a constant size no matter what. I haven't changed anything between the attached pictures, but still there's something going on. As a reference, the circle image is supposed to fill the big circle outline.
So, it works on the homescreen, but not in the preview.