Submit a ticket online

or you can simply email
Give as much detail as possible including - name of app? - what is the error message? - how to reproduce? - where is the file located? - what have you tried?

You can send us a screenshot of the error. On your keyboard, press
⌘ ⇧ 4 

Then use the crosshairs to drag across the bit you want to send. After you release the mouse button, the screenshot will be on your Desktop and called
Screen Shot {date&Time}.png
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