50D can't use SET button "the Canon way"

[gkuenning]

I have the ML 2.3 stable release on my 50D (firmware 1.0.9 as recommended).  Before I installed ML, I had the SET button configured to let me quickly choose different picture qualities (esp. RAW vs. JPEG).  Now, when I press SET the blue light blinks but nothing else happens.  I made sure I have "Use SET button" turned off in Prefs->Arrow/SET shortcuts but that doesn't seem to help.  (I also tried turning it on in case I misunderstood the setting.)

The SET button does work "the Canon way" in Live View.  It also works the way I want when I boot without ML.

Based on previous ML experience, I'm assuming that I have some conflicting setting.  Any suggestions on what it might be?