Looks good!
One question here. Will your spline always be a circle in this case? Or do you need the letters to follow a more complex path?
If it’s just a circle, it would be much easier (and more performant) to rotate the whole spline rather than make the letter slide along it.
For something that simple, you may just need to add a Rotating Movement component to the actor and set the rotational value to the desired speed. Place another actor for the second text.
If you need to use a single actor for both pieces of text, that can be done, too. You will need to duplicate the letters loops - wrap them with another loop.