If you are not afraid of doing own research and thinking logically filling in missing bits of the solution, http://avidemux.org/smif/index.php?topic=17187.0 could give you pretty much everything needed to find your own.
Please be aware that the parameters of the Mp4 muxer have been extended since 2.7.0 release to allow to force display aspect ratio, mp4 container is generally much more restrictive than MKV WRT codecs so that conversion may easily fail.
In any case you are much better off using the latest Avidemux nightly instead of the outdated 2.7.0 release. Alternatively, use just ffmpeg directly (Avidemux adds no benefits in your use case).
Thanks got it all working BUT I get an error message, Which is below...
I have to select ok for every file loaded for it to do the conversion, The conversion works great, apart from having to select ok for every file loaded.
TinyPy: Exception
Exception : (tp_load) cant get filesize
BackTrack: File:py2bc.py,line50
Here are my Bat file Settingsset avidemux="C:\Program Files\Avidemux 2.7 - 64 bits\avidemux.exe"
for %%f in (*.mkv) do %avidemux% --load "%%f" --run pui.py --save "%%~nf.mp4" --quit
Here are my Py file Settingsadm = Avidemux()
adm.setContainer("MP4", "muxerType=0", "useAlternateMp3Tag=True", "forceAspectRatio=False", "aspectRatio=1")
Any idea what is wrong
Thanks