Save Playlist Info *Not working*

Evenin all, I need your intelligence, if you would be so kind...

I have been having this really odd issue, where i am sometimes unable to use the "save playlist info" feature. Its been doing this for sometime now for the past couple of versions of RB and open to the fact that its more maybe a issue on my system than a glitch in the RB matrix. Weirdly as i mentioned, sometimes it just works... sometimes it doesnt at all.

I try to use .txt and the .m3u8 and after clicking either of these, it does nothing. Zilch. Nuffin. 

I am using windows 10 with the latest drivers and using the most current version of RB - 5.1.1 x64... my tracks are located on a dedicated tree driver from my external NAS.

really puzzling issue and hoping that someone can make some sense of it all, really dont want to have to uninstall and re-install if needs be, just for this one feature as everything else is working perfectly well.