Your security concerns puzzle me.
Your MD data set is stored on your local computer. So I would have thought that any malicious app on your local computer can access your MD data set regardless of whether you are syncing using Dropbox Folders or Connection or not syncing the data at all.
I should have been clearer. I would like to see status when the sync data is done reading. I believe that when I start Moneydance it is reads the data from my dropbox connection in order to sync up. I have never seen any status for that on the windows desktop client.
Also, let me explain my security concern better. I don't want to allow ransomware access to the dropbox sync contents by having it mounted on my computer. If ransomware encrypts my local dataset, I can recover from dropbox. That is why I prefer to give Moneydance acceess to dropbox via dropbox connection, and not use a dropbox folder.