OSMC + Synology (with username and password)

I’m sorry to bother you but I’ve watched a lot of videos and read a lot of threads and I couldn’t solve my problem
I have installed OSMC in a Raspberry Pi 3 in order to test it. I already have a Mede8er 600 and a NAS Synology, but I can’t add folders from the NAS to a library of films. I have abled NFS in Synology, but I can’t. In Mede8er you look for net devices and when it finds the Synology it asks me for a user name and password, but there’s no way I can do that in OSMC.
Please, can you help me? Thanks in advance.

I guess reading this wiki helps