How do you clean the inside internal roof fabric without messing it up As soon as you rub it or wet it the fabric fluffs up enormously and looks out of place and doesn't return to normal
Definitely avoid any rubbing. There's a thread here with a cautionary example of the same situation. It also has a link (in the second post) to a thread about what did work for me in a 2010, which was only to dab and blot (never rub!) with a white napkin dipped in isopropyl alcohol (because the stains on mine were greasy) and clear soda water (I wanted the bubbles, to do the work I couldn't do by rubbing). Once the material has been damaged, I don't know if there's a way to fix it, short of replacement. Maybe an auto upholstery shop would have ideas.
