This is a very interesting project. Exactly the type I enjoy doing the most!
I've coded a captcha solver for a voting site before, with a proxy changer.
That program solved minteye image captchas algorithmically without the need for a captcha solver sevice. It was lucky that this client needed to vote on a site that used a solvable captcha.
In your case that shouldn't be possible, as you mentioned to use the Death by Captcha service.
It will be important to know exactly what the security measures are for votes per IP, so that the proxies can be used to its maximum but also avoiding a permanent ban on them. If you don't have this information I'll do my best to find it out.
As you want a windows application with installer I can do this project for you using C# where you will get a nice looking program with multi threads so that it can maximize the connection and the proxy list. Also, death by captcha provides an API for it, which is great!
I'm available full time for this project. Let's start this!