I know it shouldn't matter to me, but I hate word appearing karaoke, I would prefer a ball bouncing to the current word or something like that.
Anyway, I don't think Construct2 can facilitate what you want to do, simply because, first of all, it's very difficult to sync the music with the events (somebody may correct me if I'm wrong).
If you just want appearing text, you can either make many texts with fade behavior or move a transparent-semitransparent-opaque png to the right, which will may be something similar to what you're trying to do.