Problems with dismissing the View

## What did you do?

I have three major problems:

1. When presenting/dismissing my ViewController there seems to be this white background behind my 2nd ViewController but I would like to just cover my first ViewController with the 2nd without any white views.

2. My image disappears after the user starts swiping down behind my views when instead it should not change its position (preferred dismiss animation) until the view actually dismisses. Same things goes for the add-Button in the bottom right corner.

3. Like in the preferred dismiss animation my the backgroundView(lightGray View in the 2nd video) should dismiss a bit fast then the other subviews. I tried using the cascade-modifier but couldn't get that effect.

## What did you expect to happen?

This is how I would like my animation to look like: https://streamable.com/8wxco

## What happened instead?

The problem is that it looks like this: https://streamable.com/1k7fj

## General Information

* Hero Version: 1.5.0

* iOS Version(s): 11

* Swift Version: 5

* Devices/Simulators:

* Reproducible in Examples? (Yes/No):

## Demo Project

I also have this question on Stackoverflow with my code ( and bounty): https://stackoverflow.com/questions/59684779/swift-hero-animation-to-dismiss-view