Hi guys, not sure if this is appropriate place to put this but I have built a very basic test for set actor location as I was experiencing similar issues. In 4.8 there seems to be a bug with it as it works as intended in 4.7 for me. I made a basic blueprint object with physics simulated and a keypress for testing setactorlocation.
I hope this helps or that issue causing this can be identified. I am using movecomponentto as a temporary fix but it isn’t a ideal solution.