I guess that the keyboard screen is too particular for a classic Dizzy game, so you should implement it in the script, using a dialog (or something similar in the DrawHud handler).
When up and down keys will be added, a "selection cursor" could move on four directions.
Until then, you can scroll horizontaly a single line with characters, use action to select a character, have special character for delete, or accept, etc
If it turns out well, it can be posted as an article or a code pack, for others to use if need it.




