Arduino Mega and Windows 8 Tablet

Hello,
i've seen on Adafruit that arduino was supopsed to be compatible with Windows 8 tablets ; i bought a Lexus ThinkPad and an Arduino Mega, as well as a femelle usb_femelle usb cable to link both . I installed manually the Arduino driver and IDE on the tablet, and tried to run a simple program. But the Card is not recognized by the tablet. I've got a Code 10 error : Winodws says "the driver is correctly installed but the device doesn't work".
Any idea how i could solve this problem?
Thx