Molinsky try this download Andy's Tragic 7 build after you do don't change anything from it, than simply add the 50D firmware in that folder that's it. That should solve all your problems..
@Andy600 & @goldenchild9to5
Thank you so much, guys, for all the help. I'm sorry about this late reply. Unfortunately (or not), I work all day and only have the night to test everything in the camera.
I deleted everything I would not use in the card: pdf files, other cameras firmwares, config files... and it works for now after I tested some customized videos.
The thing is: I use a very crappy card. It sucks so bad, has only 29mb/s of write speed. That's why I didn't posted any test, I'm waiting (forever) for my Transcend card. It is possible this card be the reason of such instable interface overlay?