The Commonwealth Catalogue is a good resource if you are specializing in any of the older British Colonies and want something with more listings than Scott or Gibbons. Unfortunately it has not been published since 1980, so you can only find it as a used book. I see them on eBay
from time to time.
I collect British Colonies from the West Indies, and use the Commonwealth Catalogue in addition to Gibbons to look for color shades. It does help explain some of the things you find - like your two colors of Cyprus. Other than Bridger & Kay (who published the catalog), no one else lists any stamps with CW numbers.