I tried it right now and it's actually quite simple, using Blend mode effects. The capx is attached here.
1. You create a layer for both the text and the color object.
- Set "Transparent" to "yes".
- Set "Blend mode" to "source atop".
- You can now also create other layers e.g. below that layer if you want a background.
2. Create a Sprite-box for the color. (Just wide box that can cover the text's width)
- "Blend mode" of Color-box to "Source in"
3. Create your text.
- "Blend mode" of the text stays "Normal".
4. Both the text and the color-box are now on the same layer. Color-box needs to be ABOVE the text in the
I also implemented a fast movement event for the blue bar, so it can it goes to the next line after the first one is finished. The Color-box has the Bullet behavior right now.