I) I can see the window changing size directly after I dragged the window. It isn't that hard to notice.
II) To verify what I saw, I measured the size difference as follows..
A) Ran the exe, when the "game" has opened completely (finished loading) and screenshot'd it.
B) Cropped out everything except the client area, pixel-exact, which measured 640x480.
C) Dragged the window, noticing the client height changed a little based on my vision.
D) Screenshot'd the window again.
E) Cropped out everything but the client area, pixel-exact, which measured 640x484.
F) With a tool window, the height is 4 pixels off.
G) The resulted resolution change is more or less wrong based on the window type my window styler extension has assigned the window.
III) Using the same exact project, GML, and DLL, GMStudio does not share this problem.
IV) I'm on Windows 7 x86 but I'm positive this isn't the isssue
V) FYI in GMStudio window_get_width/height(), window_set_size(), and the last two args of window_set_rectangle() are based on the *client* width/height, not the border.
A) ENIGMA should do the same thing as explained in V) as it actually makes sense. Microsoft's MoveWindow idea was an epic fail. Plus it would fix GM/GMStudio incompatibilies.
B) window_get_x/y(), window_set_position() and (only) the first two arguments of window_set_rectangle() ARE based on the window border's position.
VI) That "new" portable hasn't been updated in five days, and I definately since then have downloaded and applied that update.