It might be too much to ask but, could you give us a link to your build or describe how to build a worm bin to harvest the castings? Like the one you have?
Mine is pretty simple. I have three, 7gal totes nested in each other and all sitting on another one with a lid that has a pvc pipe frame inside to hold the weight.
This bottom one has holes in the top lid to let excess liquid drain through and a spigot at the bottom which I leave open with a catch pan container to catch the drippings. I use this leachate to prime my compost pile.
The three nested totes (wish I had a fourth) are all the same and labeled so I can note any changes to inputs, etc. They each have many holes in the bottom big enough so the worms can easily migrate up and down through them. They also each have many smaller vent holes in the upper few inches of the sides to help with air flow although that's really only needed for the uppermost one in the series since when they nest there is enough side air between the totes. I also use inverted plastic cups in the bottoms of each container to prevent the material from fully compressing with the weight from the totes above.
The top one has a lid to keep it dark and the moisture in but you could easily use a wet piece of burlap or newspaper or something like that instead.
That's pretty much it.
I harvest every two months which means each tote sits for six months for the material to break down. Sometimes not everything has broken down so adding a fourth bin would allow for an extra period for more fully finished castings.
To harvest, I dump the contents out on a tarp in a pile in bright, indirect light in the breeze which causes the remaining worms to huddle in the middle bottom in a pile which makes it easy to move them to the new upper container without having to go through the castings in small handfuls.
The breeze helps to dry them out a bit making them easier to process which I do by running them through a colander to screen out the bigger stuff. A second smaller sift would allow you to screen out the egg capsules if you wanted to separate them for some reason.
They're pretty mucky at harvest, so I mix and fluff the pile with my hands periodically and once they're dry enough to go through the colander without clogging it up I screen them and store them in a container for use.
Feeding the worms is dead simple as well. We collect kitchen scraps throughout the week in a countertop composting container and I dump those contents on the top of the uppermost tote, level them out with a garden trowel, add some amendments like rock dusts, malted barley, neem meal, etc. and then cover that with a layer of compost or leaves, or something like that.
Running your kitchen scraps through a blender with some water would be better and make for faster and more finished castings but I'd have to get a dedicated blender for that which I don't have yet.
The kitchen scraps are mostly water so you won't get much of a harvest from just them, but it's the other brown organic matter you add along with them that gives you the bulk at harvest.
To start a new tote I just line the bottom of the empty container with some brown material for bedding like leaves, compost, CSPM, coco, etc., dampen it, add some starter worms and then fill as I go.
My grow is pretty small all the way around but this concept could easily be scaled up to handle larger amounts of inputs leading to a correspondingly bigger castings harvest as well.