This UI in particular is possible, because you don't have text-over-image or text-over-gradients.
I'm not sure what you mean here, both are pretty simple.
What I mean is that functions like TextOut and DrawText seem to be drawing solid color background. I might have missed something, but the last time I tried, I couldn't figure out how to draw text on an image without that solid color background. I spent a few hours trying different thing. and I finally ditched DPI. If you have solid background, it is trivially easy to draw text.