The text tool assumes a given font. If no font (either true-type or stitched) is right for what you need, you either need to make your own font and use that or create the stitching manually.
I have a font that I already have on my PC. It's a true type font so the program recognizes it. The problem is that I'm doing it smaller so having it as stitches doesn't work. I was trying to do it as backstitching instead of stitches. This way I could get a lot more out of it. Does that make sense.