Yeah, if you are simply editing the DVD MPEG video, then any kind of wipe must be added to the video, which means re-encoding. Even if you took a short segment, added a wipe in Vegas, and created an MPEG to splice back in, I think Womble requires all joined MPEGs to have the same video/auio bitrate, and that would take quite a bit or experimentation. If it only required the same resolution of all MPEGs, then you might be able to get away with it.