Hi UltraLion !
Thank you very much for your help !
I've found a solution thanks to your tips :
- create an intance variable "timelineID"
- create a timeline with the name of the sprite and the ID (exemple : "Platform_1")
- create a custom action for the Sprite "Trigger platform"
- On "Trigger platform" ➡ play the timeline by name : "Platform_"&Platform.timelineID
Works perfectly ! I just have to organize my timelines into a folder named "Platforms" now. :)