how to crop clips from a file into a new video file

first, get start the v2mixer
switch and create new project, because we just do cut so settings are doesn't matter, just "OK".
then add the the video file to layer.
just drag your file to v2mixer's layer
seek the time to start on Editor player(the left player)
click "Marker A" flag as start
seek the time to end
click "Marker B" flag as end
back to step 4, setup another Marker A and B
until all the clips are marked
click "Cut" (the scissors icon)
switch to "between Marker"
select "export all markerA to next markerB"
if you need precise timing, choose an codec but not copy(time is imprecise, but very fast)
1. such mp3 for audio, or vp9 for video, for more see Export As Movie
checked the "as one"
select(the dialog left bottom) the file where you have to save.
click "Queue" submit as job
wait the job done. (the clock icon in top main bar, the "Queue", or just wait it will flashing prompt you when done)
you will see the file in the folder you selected.