How to implement realtime camera software into my UI

We have camera-software that detects products passing by real-time. It has a basic UI, so it could run standalone. The software is written in C#, winforms by an external company, but I have the source code of it.

I have been asked to write a new UI with a nicer look and feel, without much modifying of the current camera-code. Maybe making the Camera-UI-controls accessible by setting them to Public, but not creating a new Form in it with sliders, etc.

I thought creating a new project and adding the existing camera-project to it. Then starting the camera-software by showing it as a 2nd form, like

public Form1()
{
    InitializeComponent();

    Camera.Form1 formCamera = new Camera.Form1();
    formCamera.Show();
}

This way I can access the camera-UI-controls. Now the issue is that the camera-software should have a higher priority than the UI, because it otherwise could miss products passing by.

What is the best way to get this done?