I dont have a enhanced SIM (nor do I know what it does/is) but I have installed the leaked 4.4.2 rom and the nc2 firmware. I lost data connection as well. I have the 3g/4g icon pop up but the arrows are not there and it will not connect to the internet. I have tried using mje. m19, nc4, nc2 modems to no avail. I have also tried using Hyperdrive ROM and the 4g icon wont even show up. It was working fine on my stock rom yesterday before I upgraded to KK.
Anybody with some insight on this topic, help would be greatly appreciated.
PS I searched through several forums and have not found any solid answers.