Requester station constant combinator setup

[mborbola]

Hey!
First of all thank you so much for the blueprint book it's really nice and well thought out. I have an issue however that I wasn't able to solve using the docs and the in-game blueprint descriptions. I'm using providers, sequesters, 1 depot and 1 controller.
There is 1 4-Car Train in the depot which automatically went there.
Stations are Single-Statn 4-Car Loop (+2 stacked) + Vanilla Item provide Header + 4-Car (left input) Provider

My problems is that the trains are not dispatched from the depot and I think I misconfigure something.
For the provider station I block all but 12 stacks in the first iron chest.

My questions are:

1. What do the control signals mean? A-Z
2. What do I change on the constant combinator on requester station if I set up the parameter to be ?

• Change the -1 value to -8000 or -16000? Didn't work
• Add a value to the first group (like X) with the value -8000 or -16000? Didn't work

I'm using Factorio 2.0.15 without any train mods and the blueprint book is v5.0.27.

Thanks in advance.