Easier to do this via the Q10 than Windows. If you do it from Q10 then no need for Samba or any other setting to be changed.
I would recommend installing ES File Explorer (free from Play Store). It's a much better file manager than the pre-installed one.
Navigate to the network location in ES File Explorer (under Network - LAN tab), copy the files (copy at bottom of ES File Explorer screen), navigate to the HDD in Q10 Pro (listed as sda1 at top left of ES File Explorer) and paste where you want.
Doing it using Windows is possible but you'll have to navigate Windows' difficulties with permissions (the problem you are having I think - see here: https://www.youtube.com/watch?v=nQZXEcFwp28) and then you'll have to override the destination has not enough space message (a quirk in how Samba server works from Q10 Pro.
Pixel Media Server is only for streaming via DLNA/UPNP. It won't help with file copying.