This video is on using SGB’s message controls to enable things like bold, italic, underline, font size in message windows.
The SMILE GAME BUILDER Tutorial #68: Message Control Characters (Part 1) is uploaded to YouTube. It goes through using the control characters from page 110 of the manual to insert variable and string values in messages.
Message Control Characters (Part 1) Video Tutorial
Message Control Characters (Part 2)
The next part will cover more control characters, this time messages and text decoration from page 116 of the manual.