Thanks for both replies. After turning off the Colormunki service in the Control Panel, SpectraView found the Munki just fine, and it was easy enough to turn the service back on to use the ColorMunki software.
Colormunki worked fine on my wife's Mac with OS10.6. She is using an ancient LaCie 21" CRT monitor, which we had profiled with the i1Displayii colorimeter and the HP APS software. I tried using the Munki on it using the ColorMunki software, the LCD setting, and under the advanced options I set the luminance target for 80 and let the Munki go through its paces.
The resultant profile seems to be OK. But I think we are still better off using the i1Displayii setup. Any thoughts?