Kopier problem Fantec MM-HDRL

I have a small network with the Fantec MM-HDRL (also setup as NAS), an Acer Aspire Easystore NAS (both wired), and two Laptops (Vista home)(both Wifi).
When I try to copy from the Fantec drive to the Laptops (via the remote control); it works fine. What I see the files don’t keep their original time/date, but get the time/date of copying.

When I try however to copy from the Fantec to my Acer-NAS (via the remote control), the copy command is immediately finished. On my Acer-NAS I see as result, one file with length 0. This file has the time/date of the copy moment and is read-only. If I create a new directory during copying, the directory is made without problem.
The problem lays in my opinion in the copy command. Fantec does not copy a file, but creates a file with the same name and fills it with the content. Why this file gets immediately read-only on my Acer-NAS and not on my Laptops is a mystery to me. But there lays the reason the file cannot be filled anymore, and Fantec thinks it is finished.
When I copy files from my Laptops to the Acer-NAS or Fantec-Nas and visa-versa, or via my Laptops from the Fantec-NAS directly to my Acer-NAS, I don’t have any problem. The file also keeps then it’s original date.
I can of course copy the files from the Fantec-NAS to my Acer-NAS, making use of one of the laptops. But the Acer NAS and the Fantec are in my wired network, and the Laptops are connected through Wifi. Direct copying must be factors faster, and don’t occupy a laptop.

I checked the firmware versions of the Acer NAS 2.0 and the Fantec. (nov 2009) They both have (now) the latest version I could find.

Does anyone know a solution or workarround.
I can read german, but my german is to bad for writing.