Oh, I see.
I believe you are going about it wrong.
When making GUIs, the images are shown at screen coordinates, rather than in-game coordinates.
An example would look like this:
NPC Code:
if (created || timeout){
showimg 201,guigfx.png,screenwidth-imgwidth(guigfx.png),0;
changeimgvis 201,4;
timeout = .05;
}
That would show "guigfx.png" at the upper right-hand corner of the screen all the time.