I finally decided to run the TitanUnlocker and flash back to radio 1.40, and this solved my roaming connection problems.
For those who need help, do this AT YOUR OWN RISK (and note that doing this WILL erase all your programs and data):
http://forum.xda-developers.com/show....php?p=1538775
Download and run the above unlocker (you may need to become an xda-developers member to download, and you can unpack the RAR file with a free tool like RARZilla for windows.) This will place your phone in a mode ready to flash a new ROM.
Go to QLINKS, at the top of every PPCGeeks page, and choose "open FTP site" and navigate to Titan/Radios/140_radio.rar
Download and unpack that and you'll see a RUU directory. Navigate into that directory and run the RomUpdateUtility.exe, which is already set up to flash the 1.40 radio by itself.
After you're done, reinstall your programs and data.