Scott sorry you are having issues - it is not the most obvious process. To attach a picture is a two step process but, fairly straight forward.
Click on "+Attachements and other options" shown below
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Then where it says drop files here, you can drag a JPEG/PNG - picture file - from your hard drive and drop it there.
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This is what it looks like on my Macintosh.
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My file folder is the window on the right. I have dragged the files attach.png, attach1.png to the Drop files here and they show in the Add Attachment area below.
Let me know if this is unclear or does not answer your question.
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