Audi A4 S-line Avant 2.0T FSI
If the scratches are minor on the dash and glove box try using a heat gn like what you would use to strip paint at home.
Build up the heat gently and you will see scratches change in front of you. Normally when plastic gets scratched it goes what we call 'abit furry'. The heat gets to these bits first and ruduces them. You'll see what I mean when you try it. Just heat it up like you missus drys her hair, not too close and keep it moving. Do not direct heat in one place if scratches do not dissapear as this method is for minor scratching only and will not do much for deeper ones. You'll be suprised how affective this is. I'm in the trade so I have used this method many times over the years. It applies to all plastic really, boot areas, door trims etc.
As for rubber coatings it's replacement only I'm affraid. You could remove trim and take off entire coating and repaint with a plastic aerosol coating of same interior colour but yu could ruin it if you don't know what your doing. Try Audi to see how much a new part would be as I'm often supprised how cheap they can be.
Hope this is of help to you, Craig
If it's got t*ts or wheels, it's TROUBLE!