Unreal Engine 5.1 has introduced either a new bug or some intended code changes to the “Set Position in Viewport” node which essentially makes it unusable at this point. You can follow other reports of this issue here: set position in viewport widget not working
The Floating Damage Texts rely on the aforementioned node to update the position in the viewport during its motion, and as a result, don’t work as intended in UE5.1 (works perfectly fine in previous versions including 5.0). Since we have no way of knowing if there will be a fix in the near future, I’ve decided to make add my own fix to the product.
Edit: The update has gone live on the Marketplace. I’ve also tested it in 5.2 and the new solution seems to be working quite fine. The 5.2 edition has been submitted to the marketplace team and should be available on the Marketplace soon.