Goto 'File'> 'Configuration' > 'Pile up tracks'

Set the maximum height to whatever you want it to be.

The GenomeView configuration directory, this directory is named .genomeview and resides in your home directory. On a *nix system your home directory is typically located at /home/username. On Window XP it is found at C:\Documents and Settings\username.

If you have trouble finding this directory, you can start GenomeView, goto to the 'Help' menu and click 'About'. Near the bottom of that dialog it shows the path where to find the configuration file.