URGENT - How to change color of the cloth floating and different colors in the background ?

Hello,

I would like to make a logo change effect.
I would like our current logo (or the one we will call the old logo) to appear at the beginning of the video and then the veil falls over it to hide it and reveal the new logo.
This part is easy, I have just a problem with the size and I would like to don’t have the rectangular frame effect.

How do I change the colour of the cloath floating in the following model:

What surprises me in this template is that I only have one layer

Thanks.