Hello Eddie, I believe they are on holiday at Lokasoft, till August 6, but I would post the question at the forum there if I were you, so Lex can find it.
Don't know about any big opening books made for Lokasoft ChessPartner GUI. But Jeroen Noomen, now with Rybka and co. made quite a few good opening books originally in the Rebel MVS format, all hand tuned and they are available in ChessPartner's format now too. It should be possible to merge a few of these or make you own expansions of these books from Jeroen:
http://www.lokasoft.nl/download_opening_books
By the way I saw that Gandalf 5 and Rebell 11 owners can update their ChessPartner GUI to version 5.4 for free with a special program to check the registry:
http://www.lokasoft.nl/downloads.htm
At least that seems to be meant for an upgrade to 5.4 but the text mentions version 5.3 and by the name of it seems to check for version 5.2. So that is a bit confusing, not sure when Lex Loep placed this update. Don't know if it will work.
It could be that the update, if you don't have it already would work better at ICC?
I have not tried the updates with CP52regcheck.exe yet, but the other update files when I tried to install them in CP 5.3 had a few problems
running ERT so I kept using the old one.
Regards, Eelco