[AT&T Samsung Galaxy S7 Edge ROMs, Kernels, Recover] CitizenInsane:
More info on the installation of this ROM

So I went through the install process on my AT&T S7E, and I wanted to add some additional info that might help. I was running the unlocked U firmware before, and I was rooted. I had horrible performance problems. When my phone woke up from doze sometimes, I could miss a phone call because the phone just lagged so horribly. It definitely seems like a lot of other rooted users (regardless of their firmware) have been having similar problems. I think it's because the engineering kernel isn't good at all. So I don't think this

(1) I flashed the V3 version of the ROM, link here: LINK REMOVED, dev doesn't intend v3 to be flashed right now

(2) I didn't choose to wipe anything with the Flashfire app - I simply followed the instructions in the OP. Once I got to the AROMA installer, it gave me an option to wipe (without wiping the internal sd card).

(3) After the installer told me the process was complete and it was ready to be rebooted, I noticed some strange behavior. My phone rebooted several times, appearing to be in a bootloop. Eventually, the regular boot animation appeared, and I heard some strange "boot music" - not sure if that's from Samsung or the OP, but definitely annoying. After this, the SAMSUNG boot logo continued to show for 10 minutes or longer. The phone got quite warm, and didn't show many other signs of life other than the blue LED ever-so-slightly pulsing. It vibrated randomly maybe once or twice, but sure enough, just as OP said, it booted in about 15 minutes!

(4) When it booted, no mobile data. I tried toggling it off/on, rebooting, even replacing the others.xml file in /system/csc/, still nothing. Then, I made the mistake of trying to flash the CSC partition with an AT&T one I used before when I was flashing the U firmware. This caused a dm-verity check failure, and I couldn't boot into the system anymore. I had to reinstall the U firmware, then re-root it. What a *****, just to have mobile data work as normal. Once I finally got this ROM installed again, still no mobile data. But I manually configured the APN (https://www.att.com/esupport/article.html#!/wireless/KM1062162), then everything worked fine. I also ran the fixes/debloater .zip which seemed to help with some lag/thermal issues the ROM was having when I came straight from the rooted original firmware.

(5) I also noticed problems with the bloatware. I was very specific when selecting from my options in the AROMA installer - I chose to keep the Galaxy Apps app installed, and chose to remove the Samsung Gear app among others. However, the Galaxy App store was nowhere to be found on my phone, and the Gear app somehow was still there, wanting to update. Turns out the Galaxy App store was there, but it didn't appear as an app anywhere. I noticed later when I got a notification from it to update something.

(6) Even though I didn't select to change the boot animation, there's still this gaudy shutdown animation with the Echoe ROM website. I definitely appreciate the work they did on this ROM, but at least give us an option to try to make the phone's operation as "stock-like" as possible.

(7) I noticed the FM radio didn't work - it works on the AT&T version, not sure what would need to be done to fix this.

Though I've just now got it working right, I'm sure I'll uncover more interesting things as times goes on. So I'll try to post an update in a week or two once I can give the ROM a proper review. Overall, great work devs, really glad y'all brought this to the AT&T crowd.