I found the text function has been changed in 12. One thing I can't find is how to make a text box (background). What I can find are the old tutorials and they just tell making it with the composite shot.
How to make it in 12?
Text is an object, the box is just the boundary that the text exists inside. In order to have that text say on a blue box, you need to make a comp of the text and then add a new plane and mask the area you want to be your new background.
In short I do not believe you can make the text box change colour.
Film Sensei has this video that shows the way to use text in HF 12.
@Andy001z: Thanks for your tip. I am gonna give it a shot.
@DataDesign: Thanks for sharing. It's new to me, but he doesn't mention about text box in the video.
Yes, that was probably not the best choice. Take a look at this one below. He has the times of the Text info listed below the video and you can just jump to it at about 52:23. Tons of great info in the full video. Hope this is helpful
My video was for Version 10. In Version 12, the text was changed again, so the video of mine above is sort of out of date. Fortunately, Shiny Films just released a video on text in Version 12 yesterday...