Rated 5 out of 5 stars
Versions 2.1.1 and 2.1.2 do not correct work with RSS-accounts.This review is for a previous version of the add-on (2.1.1). This user has other reviews of this add-on.
Version 2.x has never supported RSS accounts. You'll want the latest builds from Bitbucket for that.
EDIT: Nevermind, there is a bug, which I'll fix and update things shortly. Unfortunately, I was hoping to have Mail Summaries 3.0 ready in time for TB24 where all these issues were fixed, but I didn't have time.
EDITx2: Fixed in 2.1.3.