The use of .ctg books in any interface with the standalone Aquarium adapter

Many computer chess amateurs like to tune and use opening books in the chessbase .ctg format.
Unfortunately this format is a close proprietary one the specifications of which are not public.
So until recently it was impossible to use .ctg books with anything else than chessbase commercial GUIs.
But now thanks to the ChessOK company -the makers of Aquarium DBMS and rybka-oriented GUI - who made it available for free, there is an utility that makes it possible to use any ctg book within any UCI-compliant GUI (the same is true for Aquarium-made books in their own .hsh format).
For this you need the standalone version of their adaptor (available here http://chessok.com/download/Aquarium/BookAdapterAquarium.zip) and either the full Aquarium program or the free demo available here (http://chessok.com/demo/Aquarium/AquariumDemoSetup.exe).
You will use Aquarium to build a configuration file for your ctg book.
Then the adaptor has its own GUI for adjusting various parameters regarding actual book use and selected engine. Finally you install the adaptor itself as a pseudo-engine in the GUI of your choice.
For a more detailed explanation you should have a look here (Charles Brown's excellent How-To in the Winboard forum - http://www.open-aurec.com/wbforum/viewtopic.php?f=2&t=50318) and there (Aquarium Book Adapter page by Felix Kling on Rybka's site - http://rybkachess.com/index.php?auswahl=Book+Adapter).