I have found your problem.
In the code near the top is this ;
Code:
// ## Paul M - Flashchat - Who is in the chat v2.10 ## //
// ## Make sure the folder name defined below is the correct name of your flashchat installation folder ## //
$fcfolder = 'flashchat';
You haven't edited this variable to "chat" rather than "flashchat" - So the hack is still looking at your old flashchat, which I discovered is still installed. If I log into the old version it shows me on the forumhome.