The module needs to be fast. If it has to be 500KB for a simple label, so be it. As long as it doesn't do a lot of RAM hogging compared to others, it's fine.

If xLabel can do this, let me know:
One box that is a grip to move it all about. One square box under/over/left/right of it that is a shade/popup button. One box that has a module display, let's say for VWM.
The VWM box has the grip to the right, and the shade button on bottom. The grip image must be sized to the VWM box's height - the grip's width. Then the shade button is place at the same X as the grip, and down the grip's height, so as to appear a complete bar. All of the dimensions may be changed, so making images with a blank space the height of the shade button wouldn't work.

With a 'flat' image, this would be no sweat. One big bar, a shade label, and then a label above it encompassing the bottom border. But doing that now stands out.

At the moment, I don't see how this is possible with xLabel. xLabel is close to replacing LsBox, and being able to move it relative to its current position (being able to resize up and to the left, among other things), it will make LsBox about obsolete as soon as labels can be dragged around the screen as a group (docking).