No Web Interface - Frontview gone ;-( on my ReadyNAS Pro

Okay I shut have read until the end*, but I dit not. I (tryed) to install Pi-Hole on my ReadyNAS PRO with 6.9.6 

 (*= Pi-Hole Web Interface also uses http://ip-nas.local/admin -> yes realy BAD!)

So now I have a NAS with no Access to the Web GUI, No Problem because I still have SSH (lucky) enabled, I thought...

I worked me through the hole forum and all external links. I tryed all (I think), to Fix the GUI. Plex, NextCloud, Docker, FileSharing, NetDATA all still works, but...(data stil here)

Strange is that I can some how not DOWNLOAD (BackUP) any Data from the NAS or just the folders than it starts to hang. But this ist the realy strange thing is, UPLOADING to the NAS no Problem - 110MB/s!!! Okay I know BackUP:-/ it is not the Data, I spend hours to sort the Data and uploades to this NAS (that has new Disk in it). So then i can Factory Reset the other (older) NAS and install also some new Disks or just use it as BACK-UP (grrrrrrrr!!!). 

Okay i tryed first this (with SSH - here still on NasOS 6.9.6):

# apt-get dist-upgrade (and the apt-get udate --fix-missing and apt-get upgrade --fix-missing)

this fixed some Debian things and updated a lot but dit not fix my problem...

Then I found this  (with SSH - here the Upgrade from ):

# cd /var/readynasd
# wget http://www.downloads.netgear.com/files/GDC/READYNAS-300/ReadyNASOS-6.10.3-x86_64.zip
# unzip R*.zip
# rm *.html *.zip
# echo /var/readynasd/ReadyNASOS-6.10.3-x86_64.img > /etc/.flash_update
# rn_shutdown -r

this updated my NAS to 6.10.3 and Frontview was still not working...

Then I found this  (with SSH - here the Upgrade from ):

# touch /.os_update
# rn_shutdown -r

dit what it was told, but still no working Frontview... ;-( but ReadyNAS 6.10.3 Running, but still no way to download files (fast).

-> In Plex, I was able to Download folders, but just with 5-10MB/s  what by 400GB Data will take ages...;-( but all the other stuff that is not in Plex is still lost...

So I just have the FACTORY Reset or?:smileyfrustrated:

Factory default:

# touch /.os_install

# rn_shutdown -r

I still think I can FIX This... would it be possible if i just take out all the Disk, install a Fresh NasOS on a empty Disk, SSH in on the NAS, copy the Folder where the stuff is (see Pic) and take alls what is in the fresh install and copy it to my Frontview folder and replace it what is there? Or is there a only Fix Frontview batch? And I also tryed to uninstall Pi-Hole -> # pihole uninstall (I think is not working becouse it dit never finish the installation, so no luck there...:-() :smileyfrustrated:

Or is there a ReadyNAS User or Master how is with the force and guide me to the solution?

-> and yes Pi-Hole will be never installed on my ReadyNAS!

So stay save and healthy, stay Home to figth Corona...