17 RC4 Windows Store App & NAS permissions

I don’t know if anyone else is experiencing this.

I currently have two instances of KODI 17 RC4 installed – the ‘normal’ Windows install, and also the new Windows Store option.
The normal Windows install is fine, however the Windows Store instance cannot access any network storage location – it repeatedly requests user name/password for the network location, even if the correct credentials are entered.
I’ve checked the obvious stuff like Firewall issues – its definitely not that.

Is anyone else experiencing this?