Below there are some technical responses that you may or may not wish to test (claiming of interest, etc.). But if I'm asked this question by an authority, I view it simply through the loan application you must complete. In the declarations section, question M, "Have you had an ownership interest in a property in the last three years?" You then have a choice, yes or no. If you are on the title of real property --- any real property --- in my book, that's a "yes." If you want to answer "no" and defend that if questioned, have a very good answer ready to go.
At the end of the day, ask yourself the benefit of being a first-time buyer for the loan type you seek, versus the ramifications for not being truthful on your application. Often the calculation is much easier than you think....