Status update is yes the same as post. I should have made that clearer. I meant to post your status update like you would on Twitter a more friendly chatty post.
With regards to formatting I either copy from my word document where I wrote the original post or go through and delete the additional spaces. It depends how you write posts I rarely write straight to Medium, I have lost too many posts that way.
In the settings on Medium you can link your twitter and Facebook profile then when you publish it is just a click of the little bird. I wish you could have a different twitter account for each publication, but I don’t think you can. Hope that all helps.