iTunes Server-Why I cannot access my NAS SLibrary in iTunes?

[stylianosp]

In iTunes, I cannot access my "Music" NAS folder under the "Shared" and I would like to understand what I set-up wrong.
I have connected the AS-606T to my home network (a server with Small Business Server 2011 and 5 client PCs with Win8 Pro). I followed the instructions and I set-up the domain users and their access rights using the Active Directory option under the Access Control App. I moved to my NAS 'Music" folder about 1TB of mp3 music and selected/named this folder as my "HOME Library" in the iTunes Server app. Now, although, when I open the iTunes program in my client PCs, I see the "HOME Library" under the SHARED folders (together with HOME SHARING) but when I click to it I receive a message 'Loading HOME Library" but after approx. 5 minutes the operation stops without bringing any songs to view/listen. In short, I cannot access my song library in iTunes under SHARED. I thought that that was the purpose of the iTunes Server, i.e. to have a shared library to access from each PC/client (if additions to this, each client will eventually access it under this shared folder). Is this correct or I have to go to the iTunes program (in each PC/client) under FILE/ADD FOLDER TO LIBRARY and select the NAS/Music folder? And If I do that what is then the purpose of the "HOME Library" under SHARED in iTunes?
Please note that all folders in 606T (e.g. media, muisc, public) can be accessed in my PC/clients via File Explorer. I can see the NAS under Network, select its folders and "Map Network Drive" with no issue which seems to me that the access rights are properly set-up in AS-606T. Also, I wonder if there any folder restriction (file/folder architecture) that I have to respect under the 'Music" folder in 606T. Right now, I have organized my music in multiple layers/folders, e.g. MUSIC MP3\ARTISTS A-D (E-F etc)\ARTIST LAST NAME\ALBUM-YEAR\Songs. Would that create a problem for NAS/iTunes in accessing the songs properly?
Any help would be much appreciated. Thank you in advance.

[sys]

I have my itunes opened in my notebook and under the Shared, I can find my AS-604T Music folder. I have not changed the Display Name, so it will appear as AS-604T Library. I got only around 4000 songs though.

I deliberately tried with 5 level of subfolders but it did not appear to be cause any issue either.