This is how to set the number of rows required by using a numberic field within the survey.
Question 1 – open number field – Ask fior the number of something required
Question 2 – open text list
Question 2 – Masking – nset(f(‘Question1’).get())
Question 2 – Trigger – Question1
Once the number is entered into the number field the screen will refresh and show the number of rows in the open text list.