STEPS TO REPRODUCE
1. Launch iClone 6
2. Apply prop Box_01 and attach it to a path
3. The constraint has four key frames: 1, 42 ,45, 100 (percentages of the path)
4. When the box gets to 42% it SUDDENLY changes to a slow speed as it crawls along to 45%

ACTUAL RESULT
Transition Curve effect disappeared when moving transform key of the path

EXPECTED RESULT
Transition Curve effect can be kept when moving transform key of the path