Why can't the online help provide a listing of the properties and methods for the control? Rad Controls for ASP did this and it was very easy to locate a property or method. I simply hate searching forums to find a particular property, especially when I don't know the name of the property.
It would make a lot of sense to place a link to the API reference under Contents - Controls - RadComboBox. You must remember that people look for information in many different ways. Most people give up if they have to search through several drop-down lists just to locate the info.
Please contact me if you would like further comments on how to make this more user-friendly.