The simple version:

• The scene needs a certain number of successes for the goblins to accomplish their goal, say 5. 
• There's no fail option built in because the game does a great job of creating success with consequences. The higher the number of successes they need, the more rolls they'll need to make and the more bad things they'll need to deal with.
• If there are multiple success options, I'll tell the players ahead of time. Something like: To herd the Froghemoth into the humans, you'll need to get 5 successes but the humans are moving forward and will see you in 4 turns. Again, there's no fail state, but there are two different kinds of success.

More detailed version:

• Treat the scene as a monster but instead of moves, you track its scenes. 
• The more task-like the scene is, the more likely I am to tell the players how many successes they'll need. Combine this with a timer and you'll get a surprising amount of strategic choices out of the players as they decide if it's worth it to stay longer.
• Here's an example; 
  • Raid the Fort: Enter the Fort, Guard on the Wall, Hidden Treasure Chest, Guard Inside the Fort, Locked Shrine 💀 Magical Guardian Awakens
    • Each one of the scene's moves are mini scenes and let the GM track the scene the same way they track a monster's  moves. They succeed on an action to climb the stone wall? Mark off Enter the Fort.
    • Additionally the scenes can be zoomed in on if needed. The Danger on the action to avoid the Guard might be Caught! meaning that the goblins don't sneak by the guard and encounter them like they would any monster. The action then zooms in on the goblins dealing with the guard.
    • Someone has a Good Idea or another way of circumventing an obstacle? Just mark it off and describe them being extra cool.
    • The scene's finishing move might never come up and that's okay, but make sure it's something that can show up in any of the other scenes.
    • Also note that the first action roll often sets up the entire scene so use it to set their position in addition to anything else that happens.

C&C welcome!