This diagram, from Chapter 5 of the book, gives a high level summary of Scotland's fiscal flows over its three levels of government.
Frankly, the diagram is rather involved and off-putting if you're not already acquainted with Scotland's fiscal intricacies. So I've produced this interactive version which is simplified in appearance but still captures all the main flows. Have a play with the sliders then click the Help tab at the top and read the Quick Start bit, and, if you wish, read the rest of Help page for gorey detail and a full list of sources.
In addition to the numbers shown on the diagram, the simulation calculates deficits for each level of government (spending less tax) and estimates of the extra interest payments they would add in future years.
Here's a brief FAQ to help demystify some parts of it.