Haha nice to see you did another one of these! I could probably help you on the Dtube image thing. My workaround is creating an account on imgur, because they can host your image on their site, and give you the HTML code needed for the video. For some reason, Dtube likes to crop your images.

It's hard to explain via comment, especially since I don't have a current Dtube post, but after you get the HTML code you gotta go edit your dtube post on Steemit, erase the part of the code that starts <img=src> (or something like that) and insert your new code. The image will be the correct size, and it will remain a link to Dtube. If you want, we can chat on discord or something sometime and I can show you ;)