Carbon rom is using an ion kernel if im right, ok, so after installing the latest firmware, kindly dowload the rom u wanted to use, note its very important to read the instructions of every rom, there are some that include gapps and some arent, so just download the core rom, gapps and the kernel, take note sometimes the kernel is inside the core/main rom, after downloading it, open the compressed file and just extract the file "boot.img" thats the most used name for the kernel inside the zip, extract it, inside the c:/flashtool/kernel if u want to organize it, add another folder and name it under the roms name(why? Cuz sometimes there are some special modifications in thr kernel thats only intended for that rom) now run ur flashtool in pc, now transfer the gapps and the main rom inside ur sd card, now power off ur device, back to the flashtool, select fastboot, now back to device hold the menu button down and insert the usb cable (the usb debug be sure thats on) and itll detect the fastboot option, now flash the select fastboot option under that lightning button, then select the one on the right side, there are 2 sides, select kernel, choose the kernel u just extracted from the rom, then wait for a few secs, itll be done, look at the logs in the flashtool, now turn on ur device, the kernel shows up, hold down button and tap the screen simultaneously, the cwm will boot, now the remaining instructions are inside the rom thread just follow it...
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