Hi again. Sorry for taking so long to reply. For some reason I did not get an email notification about the new reply this time. I have added something I think is similar to what you have done and I am not able to replicate your problem. Teleporting to index 0 is something that can happen if parts of the pathfinding returns 0 for some reason. Can you try to use my simple solution and check if you are still having the same issue? This is what I have added to ATBTT_PlayerController for testing purposes:
This simple blueprint in ATBTT_PlayerController switches the current unit’s range and damage between two arbitrary values each time ‘1’ is pressed and reactivates the unit. The execution pin going off to the right is connected to the “Set Current Tile Hover” part of “Display Path on Hover” to ensure that the spline showing the movement path to the target/ranged attack path is changed if appropriate.