How can I make Events+ work with ThemeForest's Mingle theme?

At http://fablab-lannion.org , we use a ThemeForest (great) theme called Mingle. Coupled with Events+, they seem to behave strangely, as I found no way to set a correct display for both the archive and single event pages. Can you help? Thanks so much! BTW, you can see events at http://fablab-lannion.org/evenements/ for the archive, and http://fablab-lannion.org/evenements/2013/11/portes-ouvertes-entreprises/ for a single event...