Thank you for detailed answer.
Unfortunately, I would not be able to help you personally, since this question is not directly related with Teltonika Networks RUT devices.
In this case, please create another query on different forum, which is meant for GPS-FM-Tavl questions:
Then my colleagues from Teltonika GPS department would be able to help you regarding this Tavl Server issue. When you will be creating new ticket on different forum, my suggestion would be to include information from your most recent answer in this ticket. That would allow you to avoid being asked same questions twice.