Credit to the "ActionScript 3.0" book by FlashGameU.com for pointers, hints, and fundamentals of coding. (And thanks to the ActionScript.org forums for everything else.)
Nanocide version 2.0 is ready, with several improvements all round. Finally, a breakthrough allowed me to get the leaderboard system to work, after endless trials involving php scripts, mySQL, and an XML file to keep the Flash window void of error messages. Go Nanomek, go!
More titles are forthcoming, but I won't abandon a game if a glaring mistake is found.
Email me if you discover a bug or have a [constructive] suggestion. Have fun!