To create such a list is only possible with scripting. There are two ways:
1. Delete all unwanted colors, collect the colors in the swatches panel and create you list with cmyk-values
2. Delete all unwanted colors, then check every color in the swatches panel, if the color is realy applied, either local, as a style … If not, delete this color also and create then your list
Since no.2 is timeconsuming for the scripter, this script will cost much more than no.1
So if you have only one document and 50 pages, do it by hand. If you have one document and 200 pages, choose no.1 and live with some wrong results? If you need this for 5 documents with 200 pages, choose no.2.
If you interested in a paid version, you can mail me at [email protected]
Kai