PHP/Java Script Modifications

I have an existing chat/whiteboard program that I need modified. The existing script displays a whiteboard where individuals can post papers in Word format on the left of the screen, and a chat interface on the right where users can "talk". I need to make the following modifications to this program: 1. Sometimes the screen goes blank, forcing those using the application to close the window and start again. Other times, the system remains blank when someone logs in. I need someone to work through the code, find what is causing this, and fix it. 2. Right now, the chat scrolls from top to bottom. I need the chat to scroll from bottom to top. 3. Right now, the system e-mails a copy of the chat/whiteboard to whatever e-mail is listed on the account. I need the system to instead ask what e-mail address the chat should be sent to. 4. Right now, when a user enters a Word document and begins to edit it, the other participants see strange characters appear (quotes become question marks, bullets become question marks, etc.). This needs resolved. 5. I would also like the script overall looked at and optimized in any way possible. It will take some time to work through the existing code, so please bid accordingly. Thanks!