I don't know what SpikroddNG's problems are with challenge 5... i beat it in one try. keep moving to each of the four corners in turn, staying mobile. however challenge 4 is the bane of my existence.
What really bus m about challenge 4 is that if you fail, it takes forever for the Dragon to finish off the Shield. There should be a quit or restart button at the side for if you get into an unwinnable situation.
Kitty2310, your connection to Kongregate might have gone wrong, check your connection is working by looking at the little light next to the mute/unmute chat button. If it's red then the server can't read your stats.
I think the crab thing you're on about is the 'Cutybunny'. You get it by hacking a bush near the empty pedestal close to your house. The big moth is the butterfly which is in a dungeon (can't remember which).
If you buy the chainsaw it doesn't ruin the game, you can press q and e to scroll up and down through the different weapons you've bought. It says that right at the beginning in the window you close.
 "Areas"){kind=icon}
 "Bot Arena 3"){kind=icon}
 "Hero's Arms"){kind=icon}
 "Penguinz"){kind=icon}