They do still work, you just have to include the ' in the code, so it would be as follows

CLUAConsole:CreateItem('BOOK03')

Its not that complicated. Just add the following line (in a similar fashion you see it in the ini file) under the game options:
'Game Options', 'Cheats', '1',
And you can activate the console by pressing Ctrl + Space (or Alt Gr + Space).

All BG and BG TotSC codes are included plus multiple BG 2 items codes (like amulet of life protection/proof against poison/warding/power, bracers of defense 3/4/5, leather armor protector of the second/Karajah's armor, weapons like the root of problems/wakizashis/ninjatos and many more things).

The book (manual) codes are the following:
+1 Con - BOOK03
+1 STR - BOOK04
+1 DEX - BOOK05
+1 INT - BOOK06
+1 CHA - BOOK07
+1 WIS - BOOK08

If you use the CLUAConsole:CreateItem("BOOK04", X) cheat, you get X piece of +1 STR manual in one package (X is a number which is greater than 1). So if you add the , 5 after " of the item code, you get 5 items. Ideal to gain large amount of ammo (bolts, bullets, arrows), potions, scrolls or manuals with a single cheat.

forum.baldursgate.com/discussion/8165/savegame-or-character-editor-compatibility-shadowkeeper-instructions-in-3rd-post