I, too, encountered this problem. I agree with the conclusion that this is an unfortunate product issue and a was a real pain to deal with.
That being said, for the benefit of anyone else who comes across this question in the future, I can confirm that this workaround does seem to be an appropriate way to account for unearned income that was received while a resident in another state/country according to MA's instructions for 2018 Form 1-NR/PY. See page 33 of <a rel="nofollow" target="_blank" href="
https://www.mass.gov/files/documents/2019/02/25/dor-2018-form-1-nrpy-inst.pdf">https://www.mass.gov/...> for details.
