Help with Sliders

I think your problem is on slide 3.2. At least, that's the one I looked at.  One thing that  makes it difficult to get the effect I think you want is that every time you change layers, the new slider is set to 1, even if it is layer 3, or 4, or whichever. The solution is to set all the sliders to use the same variable. I set them to use slider 1.

On slide 3.3, I made some other changes that I think enhance the effect.

I deleted the sliders on the layers, and used one slider on the base layer. Notice on each layer that I have set everything on the base except the slider to invisible. I would prefer to move the slider down into the gray area at the bottom, but I realize it may be part of your sanctioned branding, so I didn't.

I found that the distance required in moving the slider far enough to see results is so large that I felt I was doing something wrong because nothing happened. I added some visual clues to the slider that may help.

I really don't like the fade transition on slide 3.2, so I removed it on 3.3.

Take the changes for what they are worth, and use any or none of them on either slide 3.2 or 3.3.