Placing a chord symbol in the middle of a note duration

If a 4/4 measure contains a whole note, placing a chord symbol above the note, then hitting allows you to put another chord in the middle of the bar, ie where the third quarter note would be.

But how about in the two pieces attached?

In the last bar of "I Saw Three Ships", the D7 presumably goes on the third eighth note. A after entering the C moves right on to the forth eighth note. I assume if I really want it to look like the attachment, I should use a quarter and eighth note tied for the C note, rather than the dotted quarter. Then a will take me to the eighth note. Does this sound right? Maybe I could even change the tied notes back to a dotted quarter once the chord is placed.

In the third measure of the third line of "O Christmas Tree", the C7 seems like it wants to be on the third quarter note. I could use the above method, or I could put the C7 on the last eighth note and use the left-arrow to nudge it to the correct position. There's no chords involved in playback mode, so I guess this is just as good. Any opinion?

Thanks...Lyle