Here is the list of known problems that have no any solutions.
Internet Explorer sometimes shows "Stack overflow at line: 0" error when loading Java files uploader Applet. This is an IE error and it doesn't influence the application or work of the uploader. Just click "ok" and continue working. After the applet will be saved in the browser cache, this error will be rare.
The error is related to ExtJs code and the latest release doesn't have this bug fixed.