I've just installed it on the latest version of WP (4.9). I get this error I've seen other people are having:

Please be reminded that there is a 5 minute cooldown when creating a Steem post in the Steem blockchain.
300 seconds left to do another post action.

I'm trying to repost my older posts first, I haven't tried with a new post. Is this a compatibility issue with 4.9?