I've tried everything.
Nothing works. I thought it would be easier to do such an usual thing. Am I missing something?
Develop games in your browser. Powerful, performant & highly capable.
I've solved by using the viewport. Here it is in case someone need.
Set position to:
X = abs(ViewportLeft("Interface") +ViewportRight("Interface"))/2
Y = abs(ViewportBottom("Interface") +ViewportTop("Interface"))/2
This will get the current min and max pixels of the screen, sum them and divide by 2 to get the center. Do it for the X and Y axis.