It got kind of crazy on chat so I hope you were able to get everything resolved. If not, here is what path I took to get going from a 3.x beta rom/radio
1. Got to boot loader (power, camera + reset)
2. Flashed a full Sprint 2.x radio/rom to my phone (
ftp://up.ppcgeeks.com/Titan/Users/stroths/ROMs)
3. Hard reset
4. Once booted up, installed 2.40 unlocker
5. Flashed full Sprint 3.x radio/rom release to get the new radio
6. Flashed custom ROM (OS portion only)
7. Hard reset