Just to clarify, Slack is a separate website and you do need a separate account. Moderators and I used to have to add everyone to our list of members, but now there is a much more convenient way to do it. Those who have chatted with us in the Slack chat room before already have an account. If you have not, please check the first post of this thread for a link. If it doesn't work, let me know.
http://mousescrappers.com/forums/showthread.php?t=16227