Hi KentE !!
Yes - nothing worked, and no - 2G was not disabled are the correct answers.
Mint 'support' had no idea why their network didn't see my unlocked phone correctly after verifying all else 'leventy-seven times, and=>
Mint has become irrelevant for me now, anyhow - as I jumped onto the Truphone SIM deal instead.
(My 'fooling around with stuff' quota has gotten all used up between Mint & FU lately !!)
I finally got my Mint Sim today after it took "ONTRAC" (who are want to get derailed) about a week to traverse the 100 miles from Costa Mesa to my front door. I have used Mint sim before without problems, but this time activation wasn't smooth, for after I received three texts, the last of which told me I soon would get another text for activating the data where I needed to input "1234" when it arrived. But it never arrived, so I tried the usual fixes and a check of the phone revealed that data was working but not incoming or outgoing calls or texts, which explains the missing text. I got the APN settings from Mint's website and entered them but calling still did not work. But from a forum, I learned that texting the 6700# with the message SETUP might work, which it apparently did and everything is working now. Mint is likely inundated with a bit too many activations of late.