Ohter things I should mention is as followed:
1.I can not transfer data using CyControl.exe,enven though I can connect the device，while I can do this using win8.1 x64 driver(perhaps this driver is not suitable)
2.I can not reemulation the device after I updated the firmware using CyControl.exe.I have to click the reconnect button to find the new device.
What is the error that you are getting? Can you print the USBDStatus and check?
Which is the driver version you are using?