It seems this update fixes the problem with regional settings: I've set my machine to half a dozen different country settings, and ScreenShotCaptor correctly starts up and preserves settings e.g. the position of the main window (haven't tested further, though).
While I'm at it, I want to report a slight but visually annoying case issue: in the "copy to clipboard" menu on the systray icon, the word "bitmap" starts with an uppercase "B" whereas all other choices are in lowercase. Similarly, in the "To clipboard" menu of the post-capture dialog, "Image" and "File" start with an uppercase letter, whereas "path "starts with a lowercase "p." This should be aligned IMVHO.
HTH