AutoComplete is the LTGRAY window on the right of the screen.  ACInit() collects words from all text files in subdirectories.   
Normally, the call to ACInit() is in HomeSys.ZC.  It provides auto-complete for typing, jump-to-code and jump-to-dictionary 
functionality.

<ALT-SHIFT-A>   Closes the LTGRAY AutoComplete window.
<ALT-a>         Opens the LTGRAY AutoComplete window.

<CTRL-SHIFT-F1> Jumps to the source code for 1st symbol in the window.
<CTRL-SHIFT-F2> Jumps to the source code for 2nd symbol in the window.
<CTRL-SHIFT-Fn> Jumps to the source code for n-th symbol in the window.
<CTRL-F1>       Autocompletes the 1st symbol in the window.
<CTRL-F2>       Autocompletes the 2nd symbol in the window.
<CTRL-Fn>       Autocompletes the n-th symbol in the window.
<CTRL-SHIFT-1>  Jumps to the dictionary for 1st symbol in the window.
<CTRL-SHIFT-2>  Jumps to the dictionary for 2nd symbol in the window.
<CTRL-SHIFT-n>  Jumps to the dictionary for n-th symbol in the window.
<CTRL-1>        Autocompletes the 1st dictionary word in the window.
<CTRL-2>        Autocompletes the 2nd dictionary word in the window.
<CTRL-n>        Autocompletes the n-th dictionary word in the window.

If you have the raw Project Gutenberg dictionary file, you can generate the ZealOS processed dictionary files with the 
stand-alone program ::/System/AutoComplete/ACDictGen.ZC.