Hi Wang,
KDS is just a version of Eclipse with extra plugins.
KDS should be detected by the USBDM installer and it will be treated in exactly the same way as any other Eclipse installation.
You can refer to this page for information on using USBDM with Eclipse:
http://usbdm.sourceforge.net/USBDM_V4.10/Freedom/html/code_sourcery_new_project.html
bye