Simple help: admin restrict to specific area

I’m reading all about Adminimize but have to admit: it seems way more complicated and I can’t quite get my brain around it yet.

Is there an ultra-simple tutorial to show me how to: take one user from my user database, and let them only see ONE specific area of the WP back-end (a custom plug-in area — let’s say Events which is managed by The Events Calendar)?

(Adminimize can do that, right? That’s pretty much all I need it to do — for several different major areas of the WP back-end.)