I don't know about psychological literature, but in common usage where I'm from, "guilt" is what you feel when you know you've done something you shouldn't, whereas "shame" is what you feel when you believe others either do or will frown on something. In that context, I think "shame" is more appropriate — essentially, it's a collection of code that brings some degree of shame to the project, not code that you should feel guilty for writing. Think, "It's a shame I had to resort to this."