[Newbies] How can I execute a script on carriage return?

I just discovered Bots Inc. and am trying to render some of the lessons within Etoys.

In Bots Incs. when you click on a Bot a balloon pop's up and when you enter text and hit <return> the text you entered is executed. How can I execute a command (do it) on <return>?

Also, I have a script that on mouse over prints:

Im a Bot. My position is: 769.5@452.5 and my direction is:34.3357941965284

How do I print integers or specify that I only want 2 digits to the right of the decimal point? (Below is my script). script1 | tmpStr | tmpStr := 'Im a Bot.\My position is: ' withCRs , self getLocation printString , '\and my direction is:' withCRs , self getHeading printString. self sayText: tmpStr

Thanks, Stephen