You have defined the spawn times by a tick count. The ticks are being calculated before the gameplay layout is set active. This means, even before you are in play mode, your enemies are spawning. You can easily fix this by adding a family with all the enemies, arrows and the prince/princess and on start of layout, destroying them. That way, the level will start fresh.
How do I add a family? If possible can you add an image too please? Thanks.
Edit: Just figured out how to add a family via tutorial.
Edit2: I just added the "destroy family" event on a start of layout condition and the sprite stampede is still happening.