The game saves very frequently - every time you start a new wave, and when you build, upgrade or sell a tower. It will only fail if the browser process is ended unexpectedly for some reason (like cutting the power) while half-way through saving. I can't help you then. In other news - added kills to the high scores (it was there all the time, but I marked it as 'hidden' for some reason)
I believe the glitch is due to me updating the game with new tower prices. After the update, it was possible that some previously built towers were too expensive, so the upgrades were cheaper (in some cases, negative). I could be wrong, because I've never been able to duplicate the bug.
Sorry, but hippodarren was right. Towers shouldn't have different costs when they're upgraded in a different order. Fixed now, I hope. Pheonix, armour on the armoured creeps is 10% of their starting hitpoints.
I wonder if Kong's servers are patchy today? Some players have recorded scores and Kong's test function works fine when I run it offline. The game will record your best score and send it to Kong repeatedly until you close the browser.
High scores seem to be reporting intermittently. I've changed it so the game keeps spamming Kong with your best score, so it should be bit more robust.
You might have to re-run that maze, maxie. The scores are only reported to Kong once, and I'm not checking if the API is online before it reports. If this starts happening to lots of people, I could make the reporting a bit more thorough.
The sequel has a fast forward button but its rating is lower. Clearly this is because the sequel has a fast forward button, but doesn't really need one.
That's a new one to me. Lenstar is on the cutting edge of mouse-maze bug detection. It is possible that my original design parameters for this game have been exceeded. Just a bit.
A couple minor changes have been made. I'm sure no-one will break the game now. ('no-one could possibly get more than 20 cross-overs anyway' - unknown programmer, August 2009).