In the Programs to start field, you specify the program that is to be opened and the respective line content "processed" if necessary. %DIR% uses the last file passed, %NAME% takes the name of the respective file. If the Call for each file [Prompt for each file] option is activated, the program is always restarted with each line passed, otherwise it is only called once at the end of the batch.
In the Log file field you can apply a directory into which corresponding protocols can be entered in case of errors.