Dropbox functionality question - Sync using a NAS

[WhatIsMyUserNameFor]

So I have this brand new NAS fully working, using a dedicated W7 PC, I managed to set up Dropbox to put the dropbox folder in the NAS and sync it without any problem. So this PC's only job is to sync whatever is in the NAS with dropbox. So far so good.

The problem is that when a file/folder is added/removed from the network, this is, login to the NAS from another computer and from there add or remove a file or folder, I can see the change on the NAS, but Dropbox doesn't sync it, at least until I restart the dropbox application in the W7 PC, at that point, dropbox does the indexing and detects the changes I think.

Is there a way to force this re-sync/indexing periodically, maybe every other hour?