Hi Neil!
Yes, I have used it on carpet and walls, curtains and cloth blinds (the one above the kitchen sink was real ugly but it looks great now!) and on the ceiling, inside the cabinets and even ON the cabinets due to over-spray (with NO problems), so literally everywhere! Lol! It works great! No stain has ever come back and there has been no discoloration of any fabric or carpet, either. We had a leak from the tv antena this last fall andnow that it is fixed I am chomping at the bit to remove the stain it left on the under panel of the electonics cabinet! I know the folex will do the trick!
I have noticed that it doesn't work too well on ink stains but it does make them slightly better. It's magical, really! Non toxic, too! Give it a try and let me know how it works for you!