Installation of WD My Cloud Home

Hi all, can anybody help a brand new user trying to understand how this WD My Cloud Home unit works?
When I went through the installation progress using the WD mobile app, it automatically backed up the photos on my phone, creating a /z: drive in the process. However, checking on Windows Explorer, the home path for the NAS drive is /MYCLOUD-HY56HE/. Checking on this, I cannot find my photos, but they do appear in My Cloud Home (Z;). Conversely, when I drag and drop music files into /MYCLOUD-HY56HE/, they dont appear in My Cloud Home (Z:). Using Sonos to play music on the NAS drive, it only finds the MYCLOUD-HY56HE location. WD Discovery software only finds the photos stored on My Cloud Hme (Z:), it does not see the music files added to MYCLOUD-HY56HE. I’m utterly confused about how the NAS drive is supposed to store files, and how I’m supposed to navigate using the software provided.
The main purpose for getting the NAS drive is to play music with Sonos, and to that end it appears to be working, but I think I’m missing out on so much more by not understanding how the software works etc.
I’ve tried downloading the WD Utilities software, but that just asks me to attach a supported WD Drive and doesn’t give me anything to add, so appears to be completely useless… Added to this, the helpline telephone numbers provided don’t work either, hence me coming to the furum for help and guidance!

@Yeshawk

Many thanks for your Swift response sbrown, I’ll read through and see if it clarifies my issues.
Best wishes

Ross