When viewing, it just shows half a stack inside the chest's. http://prntscr.com/jyurd8

My bad, I took it from the Tweaks you had already solved this. Then I noticed above the tweaks your looking to display the internal amounts.

Yeah, I added the code to enable circuits, but by default it only shows what is in the viewable slots. The way the chest stores the internal amount is 100% custom by Rseding91 and so the factorio API does not automatically read it.

Technically, it currently shows the available amount, so it could still be used to trigger when it gets to a zero count.

Factorio can still read the whole chest's content if you try to grab it but your inventory cannot contain all the stuff in it - you will get an error instead that it will tell exactly how many items are in the chest.

Yes, that is by design of the mod (by original mod author).
This thread was about using a circuit network to monitor contents for use in controlling other aspects of the game, such as inserters, belts and trains.

Unfortunately, I have not had much time for development, so I have not been able to work on this project. I have seen a few other mods out there that I have grabbed to dig into their code to find some 'inspiration', and might have some time in May to work on that.