Uh!
I understand why I got stuck in the 'Pinky Escape Room'. I tried a few things to understand and I finally found that it is because the ActionScript built in methods are no more supported by browser and the code have to be rewrote. They (Adobe) give some translation from ActionScript methods to JavaScript but it seems there's no translation for the "drag and drop" one.
I thought that Animate CC would be easier and more intuitive to build easily this kind of functions but it is not.
The good new is that, depending of what my brain will allow, I will learn a few new things in the future days/weeks :)