[Verizon Samsung Galaxy S III] TrevE:
This release adds in better support support for multicarrier. Here is my quick rant on why this all must be done right and why we spent so much time doing more than just renaming a few prop variables. Our goal is to get each carrier flashing and working on the network just like a stock build would.

The way we tackled multicarrier was from the ground up. There are many more parts of a phone that are required besides just getting a rom to boot. Your phone also needs to be able to properly talk with the network. Networks such as Sprint require additional framework in order to use SyncML (https://en.wikipedia.org/wiki/SyncML) This is important for getting any type of network "push" messages required such as Profile and PRL updates among other things. Sure, you can run for awhile without getting these but after some time you will run into issues. Sprint is not the only network with special requirements, GSM (ATT/TMO) has custom code required for SIM Activations and proper setting of Profiles that was different than VZW's CdmaLTE Activations. The list of stuff we needed to add/change goes on. Basically we are trying to make sure all these back end network things work that you may never see but are critical to a properly working device.

Besides activation stuff CSCs are also very important in the Samsung world. This required a chunk of the rom to be modified closer to the international device inorder to function properly. CSCs and other values actually set the phones Sales Code and Country Code among other things. If your devices Sales Code gets modified to the wrong network, things like kies, OTA updates, ect will be detected incorrectly. Some of these CSCs appear to actually end up written out to EFS so they will persist around, hence we wanted to be very careful. There are even code paths that are tripped for selective EFS resets and code thats messing with IMEI! (Youll probably hear more about this later...) If you end up bricking a device some of these value is written around so low it would be pretty easily detected by a bench test, short of that values sometimes will stick around improperly even after wipe. Search around XDA for all the issues that international GSM users on samsung devices face after flashing different roms with incorrect CSCs/sales codes. We do not want to run into those problems here so we tackled them first.

Lastly, regarding carrier detection and recoverys we will *not* be making it so you can select a Carrier/device for many reasons, but mostly because of how the above system works. Before the rom flashes it will show you what device recovery is telling us you are - Make sure this is proper before you continue flashing. If its not get on a proper recovery made for your device and with fully matching values before flashing our rom and you can breathe easy setup will work fine.

So to wrap everything up with a nice TL;DR, we spent a good chunk of time making sure multicarrier is done properly so you guys do not have headaches later. There might still be a few things here and there, but things seem pretty good from what we have seen so far so we are once again opening this up to the masses. Thanks goes to the whole Synergy team along with the awesome testers we had.

Enjoy the new build :)