much easier in another program (photoshop / gimp / etc) but if you rectangle select from the very top of top the image to above where you want to keep (also all the way from the left to the right of the image) then hit delete on keyboard it will remove the unwanted area. Then press the crop transparent edges button. Repeat for the bottom, left and right unwanted areas.
Hope this makes some sense ?
August 2015 - I misplaced a lot of links - I will try to find backups and repost. If You find a post that interests please reply to post with @rampackwobble and I will get a nudge!
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