Oh yeah, and your method is flawed. With your method, the player can still accidentally move or close the window as GetWindowRect returns the rectangle including window border and controls. This is not a good method of trapping the mouse.
Thanks for trying to help, but you shouldn't merely parrot back some solution you saw in another thread without thinking if it really does work.
Oh I'm soooo sorry that I am smart enough to use the search function what you should have done before posting. Now go and celebrate yourself for that plugin.
