When marking student projects, you will notice that you can choose 0%, 25%, 50%, 75%, or 100% creativity points.
This percentage amount that you can assign during marking reflects how many "creativity points" you want to award the student - this reflects how much creative modification the student has done other than challenges. The percentage amount is in reference to the base points awarded for completing the project.
The allocation of these points are up to your discretion as a coach. Keep in mind that 100% means the double the original points awarded on the project!
Example:
400 points are awarded to a student for completing a project. The coach assigns 50% Creativity Points for the students extra modifications. 50% of 400 is 200 - so 200 CP are added to the student's project, for a total of 600 points (assuming they did not also earn challenge points).
This is the only area that allows points to be awarded subjectively, based on the amount of effort a student puts into their project - which is why there's no concrete guide or rubric. Something an experienced of exceptional student might find easy (i.e., changing the colours) might require lot of effort from another student, who is less experienced, has different abilities, barriers to learning, etc... So the first type of student would not earn CP for changing the colours, but the second type of student could.
In summary, creativity points reflect the extra effort a student puts in beyond provided instructions.