It all started when I flashed the Black Box ROM 2.0.2 (http://forum.xda-developers.com/show....php?t=1834915) It flashed normally, without any problem. But, since it lacked the Xposed Framework, I installed it manually, downloading from its thread, and choosing a full install. Using the Framework I downloaded Gravity Box and the Youtube Adaway, before downloading Youtube. Since the modules needed a reboot to work, I rebooted. And this is when the bad things started to happen.
The ROM did not start. It went through the BlackBox logo, but when it appeared that the SIM unlock was going to pop up, then the phone turned off. This happened many times. So I decided to do a full wipe and install another ROM. The problem was that the phone didnīt allowed me to access the recovery.
I was using the PhilZ Touch 6, but when I pressed Volume up+Menu+Power it did not work. The only thing that worked was the Odin Menu, and I got stuck at it, I couldnīt get out the Odin Menu. So, seeing that the phone wasnt going to work anyways, I flashed a 4.3 stock ROM through Odin.
As I suspected, the ROM got stuck at boot, and got a bootloop. So then I flashed another recovery, and flashed good olī CWM. And It worked..for a while. The phone would shut down after some seconds. So then I tried to flash TWRP, but it lasted about one second and then the phone shut down again.
Since I was using Odin 3.03, I downloaded Odin 3-04 Moded Edition, from the Modem thread, and then reflashed CWM. In this time, it worked without failing, and I could do a full wipe and flashing an old Cyanogenmod 4.2.2 ROM, finally solving the problem. The day after I flashed Ultima ROM and at the moment it goes fine, without any problem. Which is weird, because it too uses Gravity Box and Xposed Modules. I even installed new modules, rebooted the phone and it works fine, without any problem.
What I want for the people here is that someone explains to me what happened, because the BlackBox ROM looked gorgeous and I wanted to give it a long try. And because I spent an entire night solving that problem, and well, I wont sleep in peace until I get to know what happened to that bastard