Yes, I did check a box. A few years back, I worked construction and was laid off during the winter. Long story short, I took a much lower paying job and had to declare bankruptcy. I attached a letter to my application explaining in more detail the reasons for the bankruptcy. I also wrote that the decision to go through with it was a very good decision on my part, as I am now debt free, and had been for quite some time before I mailed my application. I also noted that the lack of debt allowed me to return to school, and find a career that I am very happy with.
Beyond that, no other issues.