>> I forgot to say I actually use the latest Kubuntu 10.04 LTS version. (nothing changes though)
No, a lot has changed, that is your problem.
The packages required to properly run SVP on Ubuntu mandate version 16.04 or higher.
The djcj repository for example only offers mpv and vapoursynh for xenial, artful or bionic.
I mean, you could compile mpv with vapoursynth support enabled for 10.4 + all the residual stuff, but it would be easier to just use a later version of Ubuntu.
If SVP is not hooking the mpv socket you can try deleting mpvsocket from /tmp and putting this in the mpv.conf
--input-ipc-server=/tmp/mpvsocket
But this is still unreliable so what I originally did, was just opening files by having a short script point to the SVPManager executable with root privileges as default applicationt to open video file types.
Tearing in Ubuntu can be fixed by enabling TripleBuffering in the xorg.conf which can be found at /etc/X11/xorg.conf
In the "Device" section of the xorg.conf just enter the following:
Option "TripleBuffer" "True"
Should you wish to enable GPU Overclocking and Fan Control you can also enter the "Coolbits" option.
But first I advise you to upgrade your system to at least 16.04 to properly run SVP.