This issue has been closed as 'Won't Fix' due to an extended period of time without updates. If this issue is important to you please let us know by posting on the AnswerHub or UDN, and Epic will re-open the ticket for further review.
some floating point inaccuracy appear to influence actor positions when moving actors back and forth in only one axis in the level viewport. It is especially noticeable when the actors are far from the origin.
Expected: The static mesh would only move along one axis
Result: The Static mesh seems to move on two axis (depending on camera angle seemingly)
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-29908 in the post.