DT: right click a replay, Export Log.
You get a log file where you have the exact times of the things happened.
Then replay right click, Export Video, there you insert the times you want to have a movie of.
The first number is like if it is 1, then every first frame is captured, 2 = every second frame is captured... 1 = 100fps, 2 = 50fps, 4 = 25fps...
Resolution cannot be different than those your WA support while playing.
After it is done, the frames are collected in User/Capture folder. You need an application to put the frames together.
http://www.megaupload.com/?d=GOZR2IS4This is Videomach, a program just perfect for this. You simply grab the frames with your mouse and pull them in.
Rest options are all in Videomach.