Thanks Richard,

got it working

In the meantime I have another question...
I was looking for the user commands in the include and found the "DRAWLINE" ;X1,Y1,X2,Y2 , {colour} command.
However, if I want to use variable coordinates instead of constant numbers, i get an error while compiling.

The only exception is when using the variable on Y2 which compiles fine (DRAWLINE 0,0,0,J).
Is there a way i can use variables to draw a vertical line?