You cannot access
http:/10.0.0.202/berksnames/readme.html from the WAN (internet) since it is a LAN address. This is why you need a VPN connection.
However, you can still setup TNG on your local NAS and then transfer the TNG files and database to the remote NAS, although this is a bit more complicated.
First install TNG on your local NAS using a temporary database with the same name, user name and password as the remote NAS.
During the install process, you will be assigned user one automatically. Once this is completed and working you will need to create another user, one who has direct access to the LAN with the remote NAS. Assign this user administrative permission. If you do not create this extra person no one will be able to approve registrations since you are remote and will not be able to access anything in TNG until you create a VPN connection.
Now go through TNG's admin pages and adjust any settings you want for users, information displayed, images, timeline and imports etc. I'm not sure if email will work, for notifications, unless the NAS has access to the internet or a local mail server on the LAN.
After the above items are completed, manually edit the TNG config.php file and verify or modify the following to match the remote NAS variables.
$rootpath - Rename the local NAS path if the local and remote NAS paths are different. Example: /volume1/web/berksnames/"
If either of these variables are incorrect TNG won't work.
Go to you local phpMyAdmin and use the export feature to create a SQL file of the database on your local machine. To do this select the database name in the left column and then select Export from the tabs near the top of the phpMyAdmin window and select Go. A file will be created on your local drive with a SQL extension. Note: phpMYAdmin has a limitation of 1,024MiB. Since your file be be small, this will not be an issue.
Now log in to the remote NAS and open phpMyAdmin. In the left column select the empty TNG database you created earlier. Select import and browse to the local temporary database SQL file created on your local computer and select Go.
Last copy all the local TNG files to the remote NAS.
When this is complete the second user you created should be able to log on to TNG from the LAN and approve new user registrations.
Remember, only users on the same LAN as the remote NAS will have access to TNG. Users on the WAN will not. So you will not be able to access TNG from the WAN until you create a VPN connection.
When all this is complete and working, you can delete the temporary user and database from your local NAS using phpMyAadmin.