Welcome to forums.
Read
https://oss.azurewebsites.net/forum/flash...sfers-fxp.html
and
Disable FTP/SSL in the qnap apparently it could be a problem when you try to FXP in between qnaps. as described here
http://forum.qnap.com/viewtopic.php?f=185&t=24004
alternatively.
You probably need to have a play with the setting I marked on both your sitemanager sites for these servers.
Both sites must match same settings otherwise it probably wont work.
You can enable both boxes and change from direct (FXP) to Protocol independent.
A noteworthy heads up is that whne your FXP'ing normally the FlashFXP doesnt immediately display any progress since ffxp is only in between the servers and doesnt know in FXP cases whats going on with the servers, yet files may actually be transferring.
Normally it shows progress in ffxp as ??:?? and if you check in actal servers the files may be appearing there as they are transferred.