mobile

I got a T-Mobile Note 2, prepaid (so no T-Mo data, normally wifi data only) from a friend...

The device worked initially, including wifi. At some point the device had issues, and wifi stopped working, so no web, no play store. Removed the gmail account and couldn't sign back in because there is no internet connectivity even though the wifi shows as connected.

I know there are bootloader/wifi issues with the Note 2, and I need assistance on what I need to do to get the device back to rooted stock/custom rom. There are a lot of dead links around, and I am also not sure what is safe to flash because I don't know the history of the device.

As I received it:
SGH-T889
Android 4.1.1
Baseband T889UVBMD1
Kernel 3.0.31-598701 se.infra@SEP-94 #1 SMP PREEMPT Fri Nov 30 19:11:38 KST 2012
Build JRO03C.T998UVALK8

I thought I needed to upgrade to 4.3 and flash a wifi fix, but that didn't work.

Now:
Android 4.3
Baseband T889UVUCMK7
Kernel 3.0.31-2085660 se.infra@R0303-01 #1 Tue Nov 19 16:53:20 KST 2013
Build JSS15J.T889UVUCMK7

The OS loads and I can send and receive calls, but I cannot do anything with data even though wifi is connected... can't log in to gmail, play store, web, etc.

Please let me know what I can flash to get the device back to a rooted stock or custom rom with working wifi. Thanks.