Back to stock I went.
We need a moderator to close this disaster of a thread. No answer in fixing your APN settings because they don't help or fix.
In other threads, some suggested to check with your AT&T rep to be sure you still have unlimited texting with picture messages enabled.
Whomever posted this thread, should remove their link, and change the OP to - oops, this will disable some features, ESPECIALLY MMS, USE AT YOUR OWN RISK!
Since no APN settings worked, I had to run the RUU. Un-F'ing-believable.