Hi @Ian_McNamara, It’s not that hard but you just have to understand some minor things how your Synology NAS/network works. You can check SMB on you Synology under control panel, file services.
If you set up the NAS correctly just add the folder where your music is in Roon. You have to specify this folder, just adding your NAS IP address isn’t enough. Please see my help here: Nucleus not seeing Synology DS718+