In order to create a tbl file you have  to follow the instructions below
Open the attached file to your BME (all_chars.bmml)
Then go to the file menu and select the “export” item
A window opens asking you which table to associate.
Try to associate the index table. It should appear in the list, in case there is not, take the attached one.
Then the program saves the file in TXT format
Now you can print the txt file using the software you usually use to print your texts
I’m sure the first 20 characters are correct, because they are the letters of the alphabet
The next ones will be right or wrong and then it takes a lot of patience
You need to open the tbl file (you can rename one and assign a personal name )
On the left you will find the braille characters (123456 dots)on the right the corresponding Ascii file.
With patience you have to go and replace the characters that do not match your braille on BME