... My Harmony remote works fine as long as the wooden doors are open, but there is a known compatibility glitch between the HDMI IR Blaster and the Hopper, so the Harmony remote simply will not control the Hopper with the doors closed. ...
I also use Harmony 650s, with the equipment in a closed cabinet. The problem with the blaster is that Dish using a different IR modulation frequency than most. I think they do this to avoid interference from some plasma TVs. Anyway, I now use this IR blaster: Amazon product ASIN B00OVAPS3YIt's not perfect, but it works well enough. I had to play around a lot with the placement of the emitter for the hopper/joey. Too close to the IR receiver on the unit, and it won't work, same for too far away. It has to be just right.
I don't know why the amazon link isn't working. It's the
Sewell BlastIR Pro, IR Emitter and Receiver Kit, IR Extender, Supports Dual Band IR and RC-MM IR Signals
by Sewell Direct