@kasumi:
If you only did a factory reset, and didn't flash anything, you should only need to put the usbnet folder back in the userstore, the JB & usbnet hack are still 'installed', only the stuff in the userstore is gone.
But, given the fact that it's a K4, and I just fixed a few things in the K4 install process, I'd recommend just running the latest usbnet *installer*
.
(No need to uninstall anything to upgrade the stuff in this thread, not even the JB on this device).