The composite device is generally supported by Microsoft windows, but some patches are needed for muti-interface functions such as CDC & Audio. The example composite devices are tested under windows XP (SP3). For CDC serial port, additional windows driver file (CompositeCDCSerial.inf) can be found at at91lib\usb\device\composite\drv\CompositeCDCSerial.inf.
The following is alternate update to fix the composite device support on windows XP:
All the fixes for USB generic driver are included in window XP service pack 3. It can be found at http://technet.microsoft.com/zh-cn/windows/bb794714(en-us).aspx.
Two hot fixes are necessary for window to recognize the composite device correctly: