The NK Archive should now be playable again! After recent issues players had after Flash's end of life, we've been working on alternative ways to get the Archive back up and running, so you should now be able to enjoy all your old NK favourites again!
Note: Unfortunately, we can't say for certain whether this will be a permanent fix or not, as it's entirely dependent on any changes Adobe may make going forward. We'll keep an eye out for any issues, though!
Happy gaming :)