Hook up the output of the Bluray player to the projector. If that works, then you know it's the receiver. Did you do anything to the receiver? Try to remove the inputs from the receiver, connect the receiver to the projector, and see if you get an output on the projector. It sounds to me if the receiver has a configuration issue. Another thing to try is put one input into the receiver and connect the output of the receiver to the projector and see if you can get that single output working through the receiver.
The length of HDMI cable shouldn't make a difference, especially if you can connect it to the Tivo or Bluray player and everything works.