DIAdem can currently not hold text in the data area,(this will be changing) however in the mean time a variable call ExcelText1 was created when you imported this sheet. The values in the DIAdem channel "Sort" correspond to the elements in ExcelText1(x) arrary. For example ExcelText1(1) is equal to Sort, while ExcelText1(2) = Sim, and so on.
So although the text channel was not loaded into the DIAdem Data area it was loaded into a GPI variable and available for you to use in DIAdem.
Hope this helps
Tom