Motion detection in Bluecherry 2.8.8

I have a question or two. What is the purpose of frame downscale factor? In other software I have used it is not present.

What does experimental motion setting give you over default?

When setting up motion detection how is the minimum percent and frame downscale factor related?

I have looked in the manual for this info but it does not seem to be there. I can’t seem to find this in the forum has a internet search yielded results.