Was a mixture of loads of all the mentioned things. The lua part was relatively small & simple though. Few lines for each function.
1. add() -- added character to end of variable which then updates a vs value.
2. remove() -- removes last character from vs value
3. updateStr() -- updates vs value with current result string
4. clear() -- reset both vs values back to nil
5. checkAnswer() -- compared current string value of str_txt to answer of current active table index.a & return true/false actions.
All in all it was very boring to create.
Hopefully the devs will sort out true key input at some point so that all we have to do is enable a condition to switch between regular key input actions & true key input. Not sure how it would work at the minute though. In theory I believe we would have to focus on some kind of input box which is linked to a value to input text to it which would be displayed with object text. I'm not sure how else it could be done.