copy chat.php to chat.php
copy chatprocess.php to chatprocess.php
copy includes/shout.php to includes/shout.php
copy language/en/chat.php to language/en/chat.php
copy styles/subSilver/template/chat_body.html to styles/*/template/chat_body.html
copy styles/subSilver/template/shout_body.html to styles/*/template/shout_body.html
The AJAX Chat 2 directory contains those files...
It's showing you were to put them, for example chat.php goes in your forum root directory.
As does chatprocess.php
shout.php goes to your forum root/includes/ directory
/language/en/chat.php file goes to your forum root/language/en/ directory.
Handyman... I believe the instructions would be easier to understand as a MODX
Watch out! I might do a code wheelie!