@Mandy3509 This thread is quite old now. It would be better for you to start your own thread describing what happens when you try to download and any error messages you get.
This really helped me out. It definitely fixed my problems with the store bought worlds. I'm still installing the rest of the content in small increments however, this definitely fixed my worlds installations.
@antropophobic This thread is quite old, so please start a new one and describe your isssue in detail.