The download links appear to be broken for the CHM help file.
I found two commonly referenced links, both of which seem to be broken:

http://sclogic.vo.llnwd.net/o2/downloads/kixtart/help/kixhelp4.53.zip
http://www.kixtart.org/binary/docs/KiXhelp453.zip

Also, do you know if there will be an updated CHM for 4.6.x anytime soon?

Thanks,

-Tyson