Need to have Now Up to Date look outside of the Parallels container for date file

I have three computers running Now Up to Date. One of the computers is running Now Up to Date in Snow Leopard emulated in Parallels. I need all three versions to use a data file stored in Dropbox. The problem is that Dropbox no longer supports Snow Leopard. Is there a way to get Now Up to Date inside of the Parallels container to look for its data file outside the emulated environment?

 

Share Dropbox folder to Snow Leo guest system: VM configuration -> Options -> Sharing -> Custom Folders (or Share Cloud Folders ...).