Hi BinbinB,
Please check example "create_a_custom_dialog.aspx". It shows you how to create a custom dialog and insert the content into CuteEditor.
You should find the code in "Download package\Framework 2.0\HowTo\AddDialogs\cs\create_a_custom_dialog.aspx"
Online demo http://cutesoft.net/example/howto/AddDialogs/cs/create_a_custom_dialog.aspx
Regards,
ken