Grade shows only on the compacting drawer. If this is by design it should say so on the tooltip and not be applicable to regular drawers.

It's technically incomplete on normal drawers, because I've been unsatisfied with the options I've tried at this point. The obvious thing to do for now would be to disallow that upgrade on normal drawers. I'm open to ideas.

The upgrade mechanic is getting revised in the next major update. Though given your other report it looks like I'll need to deliver a bugfix release before that.

I fully understand that. The only thing that comes to my mind is doing the indicator horizontally instead of the green light, aka having the small green line fill left to right.

In a 2x2 drawer there is a small black box that I presumed was for the indicator. What if this small box was extended to the width of the 1/4 tile and then show the progress bar there?

The small black box actually predates the indicators. It's based off a design like this: http://www.qualita.co.uk/media/dynamic/img/618/1248_zoomed_cube-chest_01_zoom.jpg

Ahh, this reminded me of the paper fill indicator on paper trays as can be seen here: http://cdn3.volusion.com/76vz2.xznc6/v/vspfiles/photos/CE522A-1.jpg
That little vertical slit with the white dot about 1/3 up is the fill indicator. It works by the weight of the paper pressing down and lifting the indicator.
Perhaps something like that, but more visible?

This was resolved in 1.3.0 with an overhaul of the status upgrades. All drawers have an equivalent of the old level 3 upgrade now.