Modal Dialog windows are straightforward in FileMaker 14 (they were introduced in FileMaker 12, btw), but it's good to have it explained in a video, especially for newbies:
And for a different way to control the window, take a trip back in the time machine and check out this Modal Dialog with roll back from Soliant. It uses script triggers to freeze the action.
Or do modal dialog windows with popovers with some help from MainSpring. It takes a few tricks to make it work, but the technique prevents extra windows from opening.
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