i think youre a little confused here.
the way the posn(o0,x1,y1,x2,y2) command is set up is that the first 2 numbers give you a point, and the third and fourth do as well. theses two points are the top left and bottom right cornrs of a box.
so if you saw this:
if(posn(o0,22,100,36,112){
print("hello");
}
and you wanted to know where that was, go into picedit and find point 22,100. then find point 36,112. these points are the corners of a box on screen and that's where to go.
also, the compiler transforms if(new_room){ into if(isset(f5)){by itself. chance are the game designer wrote if(new_room){ in the first place.
its good to use defines when u r learning agi as they're way less confusing but they take ages to write. once youre more experienced you will probly not need them