As recommended by Zoo's author, ZooPlus.exp includes the pics and data files from Hydrac (explorer.PIC and explorer.DATA).

     To play with the Hydrac pics, move ExplorerGS into the ZooPlus.exp folder and double-click ExplorerGS.  Select Zoo as the game to play. (Remember to move ExplorerGS out of the ZooPlus.exp folder and back to the main Explorer directory when you are finished playing.)

     To play with the standard Explorer pics, move Zoo from ZooPlus.exp into the main Explorer directory (the one normally containing ExplorerGS) and double-click ExplorerGS. Select Zoo as the game to play.