I had an extensive exchange with Microsoft through 2013 on the following problem when using WMM to edit .m2ts clips from my Sony camcorder:

clips in which the camera has panned across (eg) a landscape are rendered jerky in WMM and this is passed on to the final DVD. Microsoft finally suggested there was a frame speed mis-match (30fps versus 25fps) and I understood a solution would be sought. Have there been any developments in the 12 months since?