DAC is indeed the Dream Avatar Creator, Irish. You're usually free to use it unless otherwise written. :D

Look carefully at each contest post by Linnea, Daria, and Neller. Linny allows you to enter the Fire AND Water categories while Daria and Neller ask that you only enter one or the other. So, two entries with the Fire and Water Color contest, only one entry for the Cosplay, and one entry for the Trick or Treat.