John, just to keep you updated: I tried using 0..149, and codes 125, 126, 127 from that .ccf file did not generate very long IR transmissions--they seemed to work normally, though they don't correspond to any function I have, so I can't be absolutely sure that they are correct. But it does appear that that was the problem.

However, using 0..149 caused IRPanels to generate *seven* panels instead of six. This isn't a problem, it seems to be just another quirkyness of IRPanels.

Regarding the 'other' program that does IRPanels' job--would it have been Hex2CCF? I stumbled across that in another thread, and gave it a try. It does the job, and the resultant .ccf file does _not_ cause UB to give three errors when opening, the way that the IRPanels .ccf files do. Hex2CCF generates only 15 buttons per panel as opposed to IRPanels' 25, so require more panels. What were those shortcommings you observed of Hex2CCF (if that indeed is the other program you mentioned)?