The manual
Eight chapters, in the order you actually work: first the configurator, then the choice groups, then prices, appearance, dependencies and everything that happens after checkout.
Reading it for the first time?
Chapters one and two carry everything else: a configurator holds streams, and a stream holds the rules. The rest can be looked up when you need it.
Something is not showing up
Then it is usually a rule, not a bug. Dependencies hide groups, the filter blocks products, and the input field never appears in the gallery.
The price is not what you expected
Prices and discounts lists the layers in order - and says what the discount threshold deliberately does not count.
Looking for one particular switch
All settings is generated from the plugin configuration itself, so it cannot drift away from it.