Required:
LinLoader - A MUST-HAVE
the EzxMpkg software- Duhhh
Follow the instructions PLEASE
LINLOADER IS REQUIRED. IF NOT IT WON'T WORK
Edit:Try not to just tap Install.lin more than once please, for me it resulted in multiple installations of the EzxMpkg software, so i had to manually uninstall all of the extras. As a piece of advise long tap then open with, it helps.
There has been many threads in the forums with noobs asking why they can't install mpkg files. The solution is in the forums itself, however its pretty hard to find.
First off, you'll need earkin's EzxMpkg software, which is probably the last hope for all of those who can't get their phones to work with the mpkg. I hope he doesn't mind me uploading it here and giving clearer instructions

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Download the ezxmpkg
UnRar/UnZip it.
You will see a folder called Installer, an MTF file, and a txt file.
Dump it all into your phone, and then tap on the Install.lin file. This will install the necessary components into the QTDownload folder in your .system place. As for the mtf file, i really did not know what to do with it, so i just let it be.
Then RESTART your phone. a very important step.
You wil then see the MPKG installer logo in the menu.
Take whatever MPKG file you want to download and rename it to a .pkg file.
Long tap, and open with the ezx-installer.
Restart your phone and that program will appear.
Credits to Earkin
Hope this will stickied for reference for all those with problems. Comments are appreciated.