In this screenshot, the text frame is bottom-aligned, but the result is that the descender on the “g” is cut off in the score.
I’m not getting that result when I test it quickly. Could an alteration of line-spacing of your text font be compressing the spacing below each line which only causes difficulty on the bottom line?
Ah, perhaps. Yes, I’m using 80% leading.
Can you change the leading of just the last line within the text block?