Open Runway, retailer of high-end, custom-made shoes and handbags, is shutting down. Open Runway, which began life as Sole Envie, was part of the movement toward mass-customization of fashion items that includes Gemvara, Blank Label, and Bow and Drape. The company was a MassChallenge finalist in 2010 as well as a Springboard participant that year. I asked co-founder and CEO Monika Desai to talk to me about Open Runway and she graciously agreed, hoping other entrepreneurs will benefit from reading …