When using complex cutters such as profile/scribe, lock mitre, corner lock and glue joint cutters, it is essential that the height of cut is spot-on to produce two halves of the joint that fit together perfectly. The first time you use the cutters, take your time with test pieces to get the two parts of the joint exactly right. When you have achieved this, cut off a short length of each test piece to use as setting pieces the next time you use the cutters. Remember to mark these with the cutter details, stock thickness etc. If the setting pieces are to be used often it will pay to make them in a close grained hardwood to resist wear.
The photo shows a profile/scribe cutter with its two setting pieces.