[Q] Phone has no signal

This is my first smart phone, I had a Asus TF700 tablet that i unlocked and did a lot of custom ROM work on. Well I am military moving back to the US soon and i was visiting to take my wife back. I bought a Verizon M8 that of course was unlocked but i was going to use t-mobile. While in the states i had the issues that is common with this setup and was losing 4g, couldnt text while on 4g, etc. At this point i flew back over to europe and thought i could use t-mobile's deal of unlimited text and data in other countries. But i dont receive a signal at all. Started looking into how to unlock and custom ROM to fix the issues. I watched all the videos and read the how-tos that i could find and did the firewater to S-off and unlock. I installed TWRP 2.7.1.0 since it was the latest on the TWRP website. I changed over to superCID. I have installed viperONE M8 ROM. I tried flashing the ATT radios that i could find in tread on the regular M8 boards but after i flashed it, it would boot up all the way, i still didnt get any bars for signal but after about 5 minutes it would just reboot. i reflashed my originial radio and it worked fine again. Well i just tried to flash the WWE radio and same thing happened. Is there something i am missing to flash radios and not have it bootloop? Also, anyone have any ideas on what i can do to get signal on my phone? I have data roaming enabled and anything else i can find about roaming enabled. Thanks for any help.