The Kryptolok series 2 uses a disc detainer lock cylinder. These are very different from conventional pin tumbler lock cylinders, and are very difficult to pick without special tools which are very different from typical lock picks.

I have four different locks with disc detainer style cylinders, and the oldest/most used one is a Master 8184D U-lock. I stopped using this lock several years ago after discovering a severe weakness in the locking pawl (can be broken with a few sharp strikes of a hammer), but the lock saw regular use for about 3 years when I loaned it to my roommate who commuted to work with his bicycle.

He occasionally had trouble getting the key to turn on it as well. The trick to getting the cylinder un-stuck was to insert the key deliberately, one cut at a time, turning the key both ways gently until there was no resistance in engaging the next cut, pushing the key further in and repeating the process until the key was completely bottomed out in the keyway, whereupon you could turn the key completely to open the lock. Basically the dirt and crud would build up inside the keyway, between the discs, and cause them to stick together but out of alignment, preventing the key from fully seating in the keyway.