Add Lead Time to a Button
When lead time is added to a code button, instances created with that button will begin a specified number of seconds before the button was activated.
Enter Edit mode in the code window.
Select the button to add lead time to and click Inspector.
Double-clicking a button will also open the Inspector.
Enter the Behaviour tab and check the box next to Custom lead time.
Enter (in seconds) your desired lead time.
You can use whole numbers or decimal numbers for lead time.