Choosing the wrong tool for the job

First of all, I need to decide what tool to use when working on my Tower Defense game. It is a 2D game, so naturally I need something that fits 2D game development. Naturally, I've decided to work with Unity.
"Unity", my friend informed me "is intended for 3D games."
"No problem" said I "I will simply create flat sprites and position them one on top of the other like a stack of cards, and then position the camera in one spot so that it will look 2 dimensional."
"That's abuse of the platform. There are great engines for 2D development."
"I'm using Unity."
"You're an idiot."
Well, he actually didn't say that, he's a polite guy. But his tone hinted it, and that's fine with me. I know Unity is the wrong tool, but the thing is, I want to learn how to use Unity.
Scratch that. I don't want to learn anything. I want to know how to use unity. The learning process is really unnecessary.
I started looking for tutorials. After an hour of hair pulling, curses and prayers, I've stumbled upon this golden link.
10 Minutes later I've bought a nice kindle version of Unity Game Development Essentials. I'm in chapter three. I already have a lush island with palm trees and a volcano.

It's fun.