Test
[IMG2=JSON]{"data-align":"none","data-size":"full","src":"http:\/\/cubeupload.com\/im\/Praeger\/M2013FiringPinCAD.jpg"}[/IMG2]
[IMG2=JSON]{"data-align":"none","data-size":"full","src":"http:\/\/cubeupload.com\/im\/Praeger\/M2013FiringPinCAD.jpg"}[/IMG2]
[IMG2=JSON]{"data-align":"none","data-size":"full","height":"530","width":"800","src":"https:\/\/i.imgur.com\/L2MqX0T.jpg"}[/IMG2]
OK, it appears that you have to unclick the "retrieve remote file" block and use the direct link (when copying from Imgur, anyway).