I had a similar problem as 1, only the delay was much less noticable. It turned out to be our Maya export which included a few too many frames for the animation (it was about 60 frames long, but the exporter used about 70), so the character would 'stick' at its final pose in the redundant frames before looping. Reducing the exported animation range manually in the exporter worked for us, so perhaps the KW exporter is doing the same with your animation.