For one, you are in the wrong section. you should be in General, not Theme Park
Anyways, if it doesn't boot until you hit enter, that is your problem.
Chameleon has two options, either a countdown and automatic boot, or no countdown/no automatic boot.
<key>Timeout</key>
<string>5</string>
will make it countdown to 5, then boot
<key>Timeout</key>
<string>0</string>
will make it skip countdown, or the lack of the timeout key/sting altogether will do that same (disable countdown.)