Please find a correct page in the safety manual for the following addition (either animations or FAQ page). Feel free to use suitable wording to explain the topic.
When using the timeline, you must specify the keyframeGroup for start and end values to ensure those are taken into account in layout animation building.
Assumptions on the implicit values do not work. Computer does only what it is told to do, it does not read minds.
You can validate your design easily with QML Scene tool. No need to put this in the manual, put recording it here, so we remember it in the future. This code snippet will change the state to default state or active state (see integration timelinetest for details)