Thank you for your answer.
This library (muzzley-...) is used for a ledstrip using SPI which is not my case.
What do you mean by GPIO toggling via linux? Is it the same thing than what I said in my first post but by doing echo 1 > /sys/class/gpio/XX/value then echo 0 > .... ?
Isn't it the same thing?
Thank you again for your help =) .