From the first page of the adventure:
The goddess Selûne has sent her priests a warning of the dangers threatening Neverwinter, and it’s up to the heroes to uncover them before it’s too late. A Living Forgotten Realms adapted adventure set in Neverwinter for characters levels 1-7. This adventure is found in Issue 193 of Dungeon online, part of D&D Insider. Dungeon issues may be found on the Wizards of the Coast website (http://wizards.com/dnd).
This adaptation document does not present adjusted stat blocks for low/high tier; any legal table of characters levels 1-7 can play, but bear in mind that the stat blocks in the adventure were written for a party of level 3-5 characters. Tables at the low end of the level band might find this adventure very difficult. At least one person at the table (either a player or the DM) must have an active subscription to D&D Insider.
We recommend that you allow at least twelve hours of playing time to complete this adventure (the equivalent of a three-round LFR adventure).