Chromatic Movement in Melody

I have some borrowed (non-diatonic) chords in my progression. I always use one melody voice to show root notes of each chord. That way, I have midi data for the tonics of each chord in my DAW. But i can seem to enter the tonic note of lets say, a flat three chord. The melodic section doesn’t seem to let you enter melody notes which aren’t within the set key, even if the melody window is in expanded mode.
Am I missing something here?

Enter a nearby diatonic note and then use . or , to adjust the pitch by semitones; see the “Non-Diatonic Melody” section of the user guide for more info.