Krylon Fusion? Really? Can anybody back that up?
Polyethylene is /in/famous about that practically nothing bonds to it. This is why it is being used for garbage cans, kitchen utensils, bottles etc. where you don't want anything to stick.
If you paint it, then the paint will only hold itself together.
It is impossible to glue PE parts with most adhesives. There is a special industrial glue made by 3M for gluing PE, but it is expensive and is available only in large batches.
One thing that you can use, though, is sticky decals. If you torch the surface very lightly with a flame before applying the decal, it will stick better.