Pledge furniture polish for the dash pad. It's carnuba wax in a petroleum distillate emulsion. The carnuba seals up the vinyl and lowers the rate of outgassing that eventually shrinks the skin, which causes stresses to built until it splits.

"New car smell" is merely vinyl outgassing, which is when the shrinkage and stress buildup starts, and heat an UV from the sun accelerates it. Keep the car covered in the sun or at least use a windshield shade.

Not sure about the CV boots. They don't see UV light (ultra enemy to organic materials), but are continuously flexed, while the car is moving. Silicone spray is probably a good as anything, but it will only protect the outside surface from various contaminants. It won't protect against fatigue from flexing. In any event, split CV boots seem to be fairly rare. I can't remember a report on this forum.

Duke