Yes, I get that Quan error also. Here is the response I received from NCH about it:
Please check that your connection on the network is not interrupted which can cause this problem. Also check that the port used by Inventoria is not blocked or intermittently blocked which could stop the sync.
Try resetting the sync with a fresh Authorization code in Inventoria and then retry.
Send us a screenshot of the error if you receive it again.
I still get the error and just live with it, though I'm not happy about it! If you find a way to get the Quan error to stop, please let me know. I'd sure appreciate it.
I also find that I have to keep a pretty close eye on the syncing and constantly double check it for errors.
I like the programs and really wished they worked properly. I think the main problem is that it's not totally compatible with the Mac. I wish there was something else out there, reasonably priced, that was.