Connecto to remote DB

I use a DB manager named SQLmaestro to connect to firebird databases. It works great! but now I need to access to remote databases located in a windows folder in computers over the internet. I have tried stablishing a vpn using teamviewer. It works great and I can open the remote folder via windows explorer. But when I try to access the remote DB I just can't do it. I attach a screenshot of my config. I need someone to accomplish the following a) Download sqlmaestro and install it in your computer. [login to view URL] b) Put the example DB in an remote internet computer. (Attached to this project, User: SYSDBA Password: masterkey) c) Stablish a tunnel -using freeware or smallcost sw- and connect from your computer to the remote DB. d) Teach me how to do it. e) Help me vía teamviewer to connect my sqlmaestro to a remote computer as an example that everything is accomplished