After downloading the various sections of the HHR service manual. I started reading the 53 page section on the cruise control (CC). Apparently the on-board computer stores the last eight times the CC was disengaged, (or failed to engage, I guess) and the scan tool can display them.

There are several pages of explanations for the various results which may be displayed. Among them is the following:

"Pedal Initialize - The PCM/ECM detects that a stop lamp pedal activation had not occurred before the cruise control system was requested."

This tells me that some time prior to engaging the CC system one must apply the brakes. Which is exactly what my CC system does.

The CC will also be disengaged by be all sorts of things including exceeding the "calibrated" speed. (What speed that might be is not stated.)

I don't think I'm going to concern myself with this issue any longer, but if anyone wants to discuss it some more I'll be here.