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Problem description:
Mouse cursor only updates position every couple of seconds making the game unplayable. This happens in both full screen and windowed modes. In window mode I can move the mouse pointer around normally outside the game window, but as soon as it enters the game window (excluding the title bar) the in-game pointer only moves in jerks with several seconds delay.

Running under Win10 (64 bit).

I eventually found that the problem was caused by the version of Java installed by the game (1.7 (64 bit)). Merely installing the latest version of Java (1.8.0_151) and disabling 1.7 in the Java control panel is not enough. You have to completely uninstall 1.7.