No you are right, maximized windows have smaller borders, smaller titlebar and cannot be moved.
I already tried to workaround the problem by storing the position and size while it's maximized, unmaximizing the window with window -r and then applying the stored size & position with /window again, the problem is that with the difference in size for the borders and titlebar is creating a gap where the window is not taking the whole screen, and the size of borders etc will vary between version of windows, you can't control this with mirc scripting alone.
