I posted tonight's EOSTalk Live announcement using the MASDACS.io test site so I could try a test to all 3 platforms at the same time and had mixed results this time so I just wanted to drop my notes here with everyone else's for future reference.
I had my post compiled and ready to go in MASDACS, and of course forgot to add my Medium token key, oops.
This gave me a chance to test saving as a draft which worked out perfectly and allowed me to pull the post back into the editor after I put in my Medium account info.
I am used to writing in HTML as well as Markdown in my Steemit posts and usually change the image markdown to basic html for my images. This allowed the images to show on Medium with no problems.
This time I ran into a similar issue others have reported, this was for Steemit and Golos. The post was sent to Medium with no problems. This was my fault since I copied my post source to Steemit really quick when I had to go back to put in my Medium key just to be sure I did not lose the post. This seems to cause a problem with the API not allowing you to create a post when the create a post form is open already on Steemit.
As has been mentioned by others, the API to Medium saves the post as a Draft and you need to manually Publish it after.
I was able to test the signature feature this time, that is pretty cool indeed.