What OS are you on?? Sounds like you need to adjust your mouse setting, particularly the mouse speed. If the mouse speed or acceleration is too much for you, then a simple nudge or bump could send the point all over.
When opening a file or trying to use the layers drop down or any of the drop downs for that matter I have to have perfectly steady hands or the arrow jumps to the wrong selection and I have to start all over again - is there any way to remedy this???
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