When I try to launch Exposure standalone, I get an error with the dll file named MSVCR120.dll. What is causing this problem?
This problem is simply caused by a missing file in your Windows system32 folder. This file is obtained by updating to Service Pack 1 via Windows Update.
To start Windows Update, tap the "Windows" key on your keyboard and type 'Windows Update" and hit enter. That should launch the program. It will then scan for updates and allow you to install anything you need. Specifically you need to look for Service Pack 1. Installing that will resolve your issue.
You can download the installer for the 2010 redistributable package from Microsoft, from here.