While it is possible to set text alignment for single cells at design time, I don't know how to replicate this programmatically.
To curstomize text in a cell of a multicolumn list box simply click in it with the labeling tool and next use the Text settings tool in the toolbar to modify the attributes of text (font, size, style, alignment and color). You are only limited in that is possible to work on a single cell at a time, not on an entire row or column. The customizations you made remain valid even after a changing text in the cell both manually and programmatically.
Regards,
Roberto
