1. You'll probably need to add the glitch tag to the DispTextStyle class as part of the custom tags. That way it'll try and add it to every letter more or less.
2. Depends on what you want to do with the swap text. You'll probably want to update the SwapText class at least to take a list of texts to do. And then tell it to keep track of which one is being shown and increment it when you want it to go to the next one. But yeah the details from there are up to how you want to do it.