add dataset existing in a NAS via url endpoint

Hi,

I am starting to get familiar with Alyx (and ONE) to promote its usage in my institution (a neuroscience lab).
I managed to install it in a server and enable the apache service, all is fine so far. What I am trying to do is the following:

1. At Alyx, In Data->DataSet->FileRecords, I aim to add a dataset that exists in a NAS (FreeNAS) by using the URL endpoint. I've been able to do so, but the option "on server" is not marked (see attachment please)
2. The idea is to "link" this dataset to a session (now the session is labeled as None, as in the attachment)
3. The final goal is to retrieve (download) the dataset in a cliente/workstation computer by using ONE-libs (python and matlab). I've seen some ONE tutorials how to print out the metadata, but I am missing how to actual download the dataset in the server.

Could you give me some guidance with this please?

Thanks,
Giuliano.