NZBGet : Search

There are extension scripts for that.

No.
There are a lot of repositories. It's not possible for me to support them individually. Instead the official nzbget download page provides universal setups. These setups work on most variants of respective OSes. For example the setup for FreeBSD most likely works on FreeNAS.

This is a hobby project on which I'm working (alone) since 2007. The development has always happened in waves. At the moment I'm more interested in other things. Unfortunately I can't tell you when and if that changes. I'm monitoring the forum and issue tracker and am ready to develop a fix for an i...

History and program state data do not take much place. It's best to keep them on the main drive.
Then there is option RequiredDir which you can use to make nzbget wait for the external drive before starting downloading.

You must have an error in the shebang. Test if you can run the script from terminal and check if it runs from correct python version.

This script uses info from file names, it doesn't communicate with web.

Which library you use? Maybe try a different one.

It should be instead of

I think the script requires python 2. Try installing python 2, then change the first line of the script to load python2 instead of python, which probably means python3 on your system.

The daemon process (nzbget itself) cannot write outside sandbox but the launcher app can. It has settings to move downloaded files after their are completed by the daemon.