Small, simple to use combination lock, ideal for large builds.
Its combination is defined by a 'server lock', so it's not only easy to change the combination, but its possible to change multiple locks at the same time.
Features:
Uses one brick name (no matter how many combo locks are made)
Uses only default events
Doesn't cause the "Too many events at once!" message to pop up (at least not yet)
Auto calibration feature
You can either download the save here, or download the marco and event saves and make one anywhere. You can get the files at this link:
http://www.mediafire.com/?ezumqnujim2EDIT: By the way, because loading events and marcos require the event saver and marco saver (no really,) they are included in the link. The Event Saver was made by Space Guy, and the Marco Saver was made by Ephialtes.