please give me some hints on how to install the newest version of plex
If your NAS is like most, you should have a package manager which allows ‘Manual Install’ .
If this is true, download the correct ASUSTOR package (ARMv7, Intel 32 bit, or Intel 64 bit) for your unit. When you have it on your computer, through their "Manual Install’ UI, you upload the file to it.
This is on page one of the Asustor forums here.
I just scrolled down a bit to find it. Didn’t even need to search.