In the event sheet called Common there is a function called, UnlockLevel. To unlock a level you will have to call this function and pass in the level you want to unlock. UnlockLevel("1") will unlock level 1.
If you look in the Levels layout you can see that each LevelSelector-object has an instance variable called level. This value has to match the name of an actual Layout, and it is also this value that should be used when unlocking levels.
In the template I have called the levels 1, 2, 3, 4, 5 ... 48 and I unlock them with UnlockLevel("1") and in the project I have Layouts that match these names, as seen in the World1, World2... directories.
Good luck with Swipe level selector and please ask again if I'm unclear