Wow! that's a lot of scripts!
You can check for obvious errors if you press ` while a video plays in mpv.
Or to enable full logs output go to mpv.conf and change this line:
#log-file=mpv.log
to
log-file=mpv.log
This will generate a log file with everything mpv does when you play something. Maybe it will give you some useful information on how to fix it.
If nothing works anymore, reinstall SVP and try again.