What is the max size. The game is set to 640x400. I try to make a GUI of 400x250, but the properties width say 320 and the height 200. Why? :-\
Because the internal game coordinates in a 640x400 game is still 320x200, you can use hires graphics on the GUI, but the dimension of the GUI cant be larger than the limit.
BTW your nick is so similar to Archangel, another member here. ;)