When right clicking a component, there appears an import command which opens a file selection dialog. You can select a txt tile containing tab separated values and the target property as a first value. E.g. if you want to import multiple values to a text label, you can make a txt file containing property name "text" as first value and then the values for each iteration separated with tab.
The Task Designer reads the values from that file to the text property of that component.
If there is an empty value (i.e. two tabs without any content between them, the system reads that as an empty value (in task that mean default value from the first iteration).
Matching the number of values and iterations can be done two ways. The easiest solution to do should be selected.
If there are more values than there are iterations, the system ignores the values after last iteration OR it can give a warning of mismatch and not accept the import. If there are less values than iterations, the system can ignore this and leave the remaining iterations empty, OR it can give a warning of mismatch and not accept the import.