In the script editor
Highlight several rows
Click on the Move Up (or Move Down) button
(side note, it would be nice if those had the Clarion IMM attribute so we could just hold the button down)
Continue to move the lines, so that they pass a section (such as [ Features ] or [ Initialize Setup ]

Observe the highlighted lines form gaps between them, mixing them in with other script lines

Bug appears in SetupBuilder version: 10.0.4929