Write a new value in %Results.ScorePercent%

Hey,

I need to write a new value into the variable "Results.ScorePercent", because I need to communicate with a LMS via the variable "cmi.core.score.raw" in the SCORM-Package. 

So I have a small JavaScript where I can successfully change the value of my own variable "MyVariable". But I can't change the value of Results.ScorePercent. 

var player = GetPlayer();

player.SetVar("Results.ScorePercent" , 12);

player.SetVar("MyVariable" , "JavaScript works");

Maybe it is possible to create an own variable that will give its value to the LMS?

Thanks for the help!