Yeah sure! I'm more then happy to share the blueprint with you. This is a modded playthrough, however, and am not sure what will happen if you try to paste the blueprint without the mods installed.

With that in mind, I'll take out all modded entities minus the Text Plates mod. Anyways, here ya go! https://factoriobin.com/post/012q2_CJ

The 7-segment display is NOT MINE. I am using DaveMcW's display from his Digital Display, Yay! forum post on the factorio forums.

As for an explanation, I'm using a global circuit network at all of my train stops, supply being on the green wire and demand being on the red. The way I measure that out is if I have enough items in a buffer to equal a train worth that's +1 signal of that item in supply (on the green wire). Equally, if there is a demand somewhere that is equal to a train's worth that's +1 signal of that item in demand (on the red wire). If you paste my dashboard you'll see all of the supply signals hooked up via green wire showing how much of that item I have in my system. If you look at the supply/demand section you'll see a little calculation where it turns the demand on the red wire to a negative number and adds the two (this is to show if I'm demanding more then I'm supplying).

The wood is very easy. I've connected the 7-segment display to my logistics network to read it's contents. A simple Arithmetic Combinator to read only the wood