It is important that players understand the core concepts of this adventure's design. This is not an adults' world where you are guests - this is your world, usurped by tyrannical giants, and you are going to take it back. To represent your powers in this world, the adults you'll face are designed in a specific way:
Their advantages
Most adults have very high Strength and Fortitude saving throws, because they are supposed to be much stronger and tougher than kids.
Most adults deal high to extreme damage, to show how easily one of their heavy blows can put you down.
Most adults have extreme defenses against Demoralize, because your attempts to scare them mid combat usually won't work.
Nearly all adults use armor and weapons made for their large size. If you, as a small kid, try to use a militsioner's sabre, you will have penalties because it's too big and heavy for you.
Your advantages
Most adults have terrible to low Reflex saving throws, to show how fast and agile kids are, and how clumsy adults are in comparison.
Most adults have terrible to moderate Will saving throws, to show how rigid, slow, or distracted their minds are (but not against Demoralize.)
Most adults have low to moderate Perception, making it hard for them to notice small, quick, or quiet kids.
Most adults have low to moderate Acrobatics skills (if they have them at all), which again shows how much faster and more agile you are.
Most adults have low to moderate Strike attack bonuses, to represent how your speed helps you dodge their clumsy swings.
The caregivers
There is one type of adult you fear most: the caregivers. An armed bandit or a chasing militsioner might even be considered a fun challenge, but an angry caregiver is something terrifying. You recognize their ultimate authority over you and fear them deeply. To show this, caregivers have extreme Intimidation and Athletics skills, representing how easily they can control and suppress you.
Fight smarter, not harder
Adults are extremely dangerous, buyt you have your ways to fight them: through cunning, cleverness, trickery, and well - who would expect a kid to be a real threat?
You should use your skills in creative ways. Why confront a militsioner in a fair fight? Use Thievery to Steal their sabre first (rolling against their low Reflex instead of Perception if you were already spotted).
Saying that, let's wrap it up: adults are dangerous, but it is them invading your world. You have your means to fight them - through cunning, guerilla warfare and trickery. You can and are encouraged to use skills creatively. Why fight a militsioner in a fair fight, if you can use Thievery to Steal their sabre first, rolling against Reflex instead of Perception if you already were spotted?
Another important thing to note: every room has something in it (might be useful, it might tell you about the world, or it might be both.) You are free to explore everything, but remember, that it is always a risk.