Hi, thanks!
Of course, that's possible, in fact, now you mention it, i should have thought about that ;)
It's been added to the version 1.0.3, which is available,
You can now inherit from any preset, drag a sprite into your object and it will be drawn behind your text (you can pass an empty string (" ") to the factory function if you want the sprite without text).
Be warry that the factory function has been changed from "GFT_Create_floating_Text_ext" to "GFT_Create_floating_Text"