Not a bad start at all. One (harmless) bug seems to be that if you shoot and move to the left or right you get a greenfoot (the default image) hanging over where you fired the bullet - any way of getting rid of it? :-)

spaceblue - you are right... it indeed lags here in the gallery... it didn't do that here offline. I changed the images to static images... try it...

wow the lagging got worse here... interesting... does anyone experience that too? Want to make sure if it is due to the code or the browser here...

ok I reverted to the previous version, not using static images. The lagging improved. Curiously, after the second reset, the lagging significantly reduced... anyone can explain that? I can only think that all resources are fully loaded into memory in eventual resets...