So i went further and started tweaking this ROM and adding stuff, and reached the point where i wanted to place the G3's Keyboard due to its resize function. I ended founding Cloudyfa's G3 Ported Keyboard and i supposed it would work perfectly (Being both ROM and Keyboard from same developer), Yet, i went for the APK installation and opened it.
1- Loads up and shows my model (D806) perfectly
2- Backup current
3- Install New & Reboot
When i rebooted, the home wouldnt stop crashing (And therefore not starting up), and i managed to open the recent-apps window, wich resulted in the systemui crashing, and rebooting the phone. It ended up breaking the ROM (The phone never booted totally, it just kept with the LG startup icon moving endlessly) and i had to go into TWRP and Re-flash the ROM to fix back up everything. (When i could load up again the keyboard screen sensor was not good and i couldnt touch the bottom keys, so i restored the backup i did and it worked great back again).
I wanted this keyboard and i certainly dont want to go back throught all the steps of re-customizing my ROM back, so how can i make this with no risks (or the least possible)?