Hmm, the lights on the front and the back of my player stay lit.

Do you mean the "standby" LED?

One known cause for the standby LED staying lit is if you have wired 12 volt power into the blue amp remote wire. But I don't think that explains your other problems.

You didn't answer my first question which was: Do you see any images on the screen at all?

Another thing worth trying is to apply an upgrade to the player (you will have to remove power and only apply power when the upgrade prompts you to do so). Maybe it's just trashed data in the flash RAM.