Here's my understanding of what happens.

If you are using a major key.... and enter the chords for that key everything lines up. The chord changes and the lead or melody will use the correct musical scale to select the notes it will play. Every thing should sound good. If you use the KEY CHANGE/TRANSPOSE to another major key, the chords will change if you selected that option and it will play in the new key.

If you change to a minor key that is the relative minor, since the scale is the identical same scale musically..... nothing changes. C to Am for example or vice versa.

If you change to a different minor.... Lets say you started in C major.... changed to Am, you would notice no change. But change the key sig to Gm or Ebm and now, you will hear some differences. NO, it will not change the chords from the ones you selected to minors.... you have to do that manually.... but it will now try to use the G minor scale for the melody scale with the chords you have selected and that might cause some dissonant sounding notes because the scale doesn't match the chords.

Hopefully that helps.

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