HELP - Error 250, MMERGE4 must be provided

I installed the MailChimp Integration plugin today and it is not working for me, but I think it has something to do with my data setup.

It's giving me an Error 250, MMERGE4 must be provided. What do I do to fix this? Could it be because the fourth item on the user info is a drop-down choice (type of user role)?

Please help! Thanks!