I kept the changes predicate (because I want persistent file storage)
we are debugging, trying to find a root cause of the problem - once we find it you can do whatever you want but for now please listen to my advices.
this line tells me that there is something wrong with your changes:
[ 25.513] (EE) Failed to load module "nvidia" (module does not exist, 0)
[ 25.513] (EE) No drivers available.
please do as follows (this time do it exactly as i write):
a) boot to 'Always Fresh' mode
b) open terminal -> switch to root with 'su' -> type 'init 3' which will bring you to the text mode
c) login as root and activate nVidia driver from /porteus/optional folder
d) run 'xconf' command and then copy /etc/X11/xorg.conf to the /root folder
e) run 'init 4' and this should bring you to the desktop with nvidia driver being used
f) if you get usual failure then please upload previously saved /root/xorg.conf and /var/log/Xorg.0.log.old to pastebin.com then link here.
Please add [Solved] to your thread title if the solution was found.