Is the hr10-250 in view of the remote or hidden away? If it's in view, are you using emitter shields to block the tivo from getting direct reception off the remote at the same time it's getting the signal from the mouse emitter?
I had EXACTLY the same problem you're describing but never knew about the IR delayed signal problem. My Tivo was off to the side of the main viewing room and IR signals could get to it. The problem was that the Tivo was seeing the signal directly off the remote and also getting the (ever so slightly) delayed signal from the mouse emitter... the two signals combined and interfered with each other and the tivo was getting garbled IR.
You have to make sure the device is seeing ONLY the IR from the mouse emitter and not let any IR leak into the tivo from the remote control in the room.
As soon as I blocked the tivo's IR window by putting a mouse emitter shield on top of the emitter, the tivo worked perfectly with my Elan panel and my Home Theater Master MX-700. It drove me absolutely nuts before we figured it out.
Xantech makes emitter shields for just this purpose:
[Link: partsexpress.com][Link: hometech.com]