Few things I've seen
-Encryption doesnt work
Ill look into it, but I know its a longrunning bug for some devices. Use access control for now. I dont actually have a GS3 so its kinda a wonder this works at all
-Tether doesnt work
Please give some more details- what mode are you in regular or fallback?
does tethering turn on and show statistics at bottom of screen? if not what does the log show inside of wifitether? if so does windows see the accesspoint?
As far as Sprint LJ7 ill download the rom and check it but answers to above will help. a logcat of it turning on and off would be most helpful I threw a bunch of debugging lines in