For every Kickstarter success there is a troubled project, and it appears as if Super Action Squad (otherwise known as Super Retro Squad) is a victim of the latter camp. After a tumultuous development process and a 2012 Kickstarter that managed to collect $53,000 ($40,000 over budget), the project is being put on hold.
Lead developer Jay Pavlina describes the situation with a heavy heart in a lengthy blog entry, noting that a number of reasons lead to the decision, including "inexperience," "lack of scope," "unrealistic estimate of cost," and "an ineffective team," among other explanations.
Since Kickstarter doesn't really offer an official refund tool, you'll have to contact Jay himself to request one -- but he does note that it's "impossible" to handle everyone right now, though it may be feasible one day. Even then since Kickstarter takes a fee, Jay would have to earn money back somehow to pay out everyone (here's a breakdown of how some of the money was spent).
The whole blog post is an interesting look into the life of an indie dev, and I encourage you to read it. Ultimately though, I feel bad for anyone who donated a significant amount of money and can't get a refund. Such is the risk of any Kickstarter.
Super Retro Squad [Kickstarter]