All great questions! I realize that it’s always difficult to make changes to your workflow, particularly when you’re running a business. However, I think you’ll be pleasantly surprised at how efficient this method is. As the owner of a cabinetmaking school, I’ve been lucky to be able to visit quite a few high end cabinet shops, so I’ve gotten to take the best practices I find and incorporate them into our curriculum and over the years have settled on a system that works pretty well and also allows for customization to meet the needs of individual cabinetmakers.
As for your questions on carcass construction, I use M7.0 x 50mm Confirmat screws such as p/n 5361C from Quickscrews.com. I simply pin the box using a pneumatic nailer together with 18 ga. nails, then use the special Confirmat countersink bit, such as this one from Woodcraft (https://www.woodcraft.com/products/7-x-50-mm-two-piece-drill-bit-for-confirmat-screws) to pre-drill the holes. CabWriter can optionally draw the pilot holes in the carcass sides which can then be drilled on the CNC. I drill these as 5mm holes because that is the size of the drill on the Confirmat countersink bit. The upper part of the countersink is 7mm, which is what the holes in the carcass sides get enlarged to. Then, you drive the screws. I buy the barrel bolts from Hafele, the part number is 267.01.715 for the sleeve, and there is a matching screw, but I don’t have the part number handy; I can get it tomorrow when I get to work. There is a link on the website for that product to the screws, but there are several lengths and I don’t remember off hand which one is the correct length.
The Confirmat screws are really amazing for their holding power and the added bonus is that you can easily disassemble the cabinet if you need to and reuse the holes with basically the same holding power. It is very important that you fully drill out the holes with the pilot bit and don’t let any sawdust stay in there as you can split the piece you’re driving into. Here are links to a couple of videos I created for my students showing the process including the barrel bolts to connect the carcasses and another one for attaching the backs. Ignore the silly alignment blocks I used to hold the carcass parts in place; our new method is to pin the carcasses together as described above.
Your last question was whether this method is hardware agnostic, and the answer is yes, assuming you’re talking about slides and hinges. Since the sides are flushed to the FF, you can use any hardware you like without build out blocks. Let me know if you were asking about something else.
I hope this answered your questions, please feel free to ask anything else that you’re wondering about as you get into it.