Where can I find documents about panel applet design?

["deng.guang" <deng guang 163 com>]

    I compiled the panel src. But I don't know how to run the new
compiled applets and how to debug a panel applet.
    The worst is I can't find useful information about the problem I
care.The documents come along with gnome is under construction. I need
your help .
    Any help will be appreciated.