Hi jake brown,
You don’t need x-particles for this configuration. This is simple to implement using the native particles emitter and dynamics, which is now bullet.
1. Make the Letters as child object of the emitter.
2. Add a rigid body tag to the emitter and make sure the inherit tag is applied to children.
3. Under the force attribute on the rigid body tag, set follow position 1.
4. Set the follow rotation to a desired figure 0 = rotation based on the rigid collision. I used 33 to give the falling letters a slight rotation whiles each faces the camera as shown in the screenshots.
5. Under the Particles attributes on the emitter set your desired speed value and add a variation to vary the speed as they fall.
6. Make sure show objects and render instance is checked.
Hope this helps. I have added a scene file for you to examine. Cheers!
This was reproduced on Cinema 4D 2023.