My litter doesn't stick to the pan. I keep two to three and a half inches of litter in each oversized pan. Did you add your 'Slide' to a smooth clean pan?
Some cats have a surprising amount of hair between their toes. My Swee'Pea gets a little trim when she's tracking a lot.
If she leaves the litter box, crosses the cleaning rug and 25' of basement floor, climbs a flight of stairs, and is STILL tracking litter when she gets up to living quarters, she needs a trim!!!
I see that litter you bought comes with a satisfaction guarantee.
Did you write to them, or just us?