3In the preferences, in the advanced, if you scroll down, you'll see power management and then that's where it times out after inactivity. That's there if you're on a laptop it tries to save the battery. If you untick that it'll just stay on. That's the way I use it.
As far as showing the text as you speak, I tried that before and there's a slight delay and I found that you're trying to read it as you're speaking and it just messes up your cadence because you're still speaking as you're reading what you just said. I'll look into that again if people seem to really want that, but in practice I found it very distracting. Is there something else that you use where that works properly and you find it to be valuable?