There are various methods to selecting multiple rows of tables within optiSLang:
Highlight a row in the table you want to select by clicking on it. Press and hold the Shift key, then click another row. All the rows in between are selected.
Highlight a row in the table you want to select by clicking on it. Press and hold the left mouse button and drag the mouse over other table rows to select them.
Press and hold the Ctrl key, then click each row individually to select it.