How to have a negative collision margin?

[RunnersNum40]

I'm working on some simulation with some CADed parts that don't have any tolerances. I'd like to prevent erratic behavior when they're put together, so I've tried to add a negative collision margin, but it causes a panic.

Is there any way to get a negative CollisionMargin to work, or to allow a small level of intersection in some other way?

[RunnersNum40]

I've found that adding this system seems to compile. However, I'm not sure if it's actually working or not. My problem hasn't being fixed, but I have some funky stuff with joints that might be an alternative cause.

fn collision_callback(mut collisions: ResMut<Collisions>) {
    collisions.retain(ignore_collision);
}

fn ignore_collision(contacts: &mut Contacts) -> bool {
    const IGNORE_THRESHOLD: f32 = 0.01;

    contacts.manifolds.iter().all(|manifold| {
        manifold
            .contacts
            .iter()
            .all(|contact| contact.penetration >= IGNORE_THRESHOLD)
    })
}