Kansas can tax non-residents only on Kansas-source income. Work income is "sourced" where the work is actually (physically) performed.
Did any of your investment income derive from Kansas sources? If so, it could be at least partially taxable by Kansas. See paragraph (h) of this Kansas statute:
http://kslegislature.org/li_2012/b2011_12/statute/079_000_0000_chapter/079_032_0000_article/079_032_...
Conversely, if none of your investment income derived from Kansas, none of it would be taxable by Kansas.
Some other possible issues: when you did your state returns in TurboTax, did you complete the non-resident Kansas return before you did your home state OK return? You must do the returns in the proper sequence in order for the program to calculate your taxes correctly. In the Personal Info section, did you list OK as your State of Residence? Did you answer NO to the question about living in another state? Did you indicate that you had Other State Income from KS?
**Answers are correct to the best of my ability but do not constitute tax or legal advice.
