Hello Javier,
As the Kinetis K60F120 and K70F120 devices shares the modules version, and TWR-K60F120M and TWR-K70FN1M has the same crystal value (50 MHz) and USB connections, you could load the provided examples for K70F120, into the K60F120, and they should work.
Additionally, you could also use Freescale MQX v4.0, which includes a BSP for TWR-K60F120M board and USB HID Device examples. This could be downloaded from www.freescale.com/mqx
After installation, the USB HID Device example projects (Mouse and CW10 for example) could be found on the
following path:
C:\Freescale\Freescale_MQX_4_0\usb\device\examples\hid\mouse\cw10\hid_mouse_dev_twrk60f120m\
Hope this information will be useful for you.
Best regards!
/Carlos