Hi there!
Have you tried clearing the update cache on the xbox 360 system? If not and you need help doing so, follow these steps:
-
Navigate to the "My xbox" slide on your dashboard.
-
Scroll right, to the last page which is the "System Settings" page.
-
Select "Memory" from the list of options.
-
Highlight your hard drive and hit Y on your controller.
-
Select the option to clear the cache and perform maintenance on the memory unit.
-
Sign out and back into xbox LIVE
-
Go back to the content on the xbox live market place and see it that content has become available.
If this is of no help then the content may be age restricted. Is your account an adult account (i.e. over the age of 18)?