Not quite. In one minute you used the portal: The cool down begins at the end of your post. With a cool down of one minute, it'll be ready at the end of your next post, and ready to use again on your post. Even if you use the skill at the beginning of your "Minute", unless you want to keep a running tally of your actions per turn, cooldown begins and/or refreshes at the end of each post.

At the beginning of your battle phase you had summoned the imp and the sword. Round one, one minute.

Second you warped in through the portal and attacked with the sword again. Round two, one minute.

Your third post has you use your portal again, despite using during your last post. One whole minute has yet to pass, as you're acting within the current minute. For all we know only ten seconds had passed.

Unless you're imply that your teleporter refreshes it's cool down each time you post, and in which case that's going to need to be adjusted.

I know using minutes to determine the actions of a fight is going to be confusing, but unless everyone would rather try to work with a [b][i]Six-Second[/i][/b] Round per Post, I'd hope you could follow the previously established method.