When the trojan is run, the desktop icons will start moving around the desktop in a formation, usually trailing around the screen in a "snake" fashion.
There are 3 different effects in the payload. After the last one, a message box appears. It reads as follows:
Icondance Maintenant tu peux réorganiser tes icônes !
Translation (from French):
Icondance Now you can rearrange your icons!
From here the icons will follow the mouse cursor until the user clicks "OK".
If the icons are auto arranged, they would just swap their positions without "dancing".