[Pharo-users] How does one use MultiColumnListModel?

Hi, I´ve been spending some time trying to figure out what to pass, and I can´t figure out what to pass to #items:. I´ve tried to pass strings, arrays of strings, arrays of arrays of strings, and the most I´ve got so far is Character(Object)>>doesNotUnderstand: #widthToDisplayInList: :S Some help or some pointers would be greatly appreciated! Cheers, Sergi