I just had the same issue. As a Mac user it's extra obnoxious because I also have to run it in a Windows virtual machine. Joy.
To get this plugin working in IE11 you have to tell your IE to pretend to be an earlier version of IE. By clicking F12 it will open the Developer Tools which allows you to change the IE version. Here is a quick video on how I did this...
http://screencast.com/t/6WXXkBeKd
Note that for me I also have to allow it to move past an error in the code that it finds and then "Allow" it to run the program.
As you can see it's a piece of cake to make this plugin work. It only takes logging into a virtual machine (for Mac users like me) and running it in IE (the crappiest of all browser). Oh, but not only that, now you have to tell IE to emulate an even older cruddier version, bypass broken code and then finally tell it that it's okay to run it, really it is. I'd almost rather stick a fork in my eye... but at least it's functional.