I love that you're trying to learn to code, that's awesome. But please learn more before you actually try to release something.
Your code doesn't even have a function, doesn't even clear ghost bricks like you says it does, and has this
(!%client.isAdmin&& $OAA:AdminLevel == 1)||(!%client.isSuperAdmin&& $OAA:AdminLevel == 2)
Registering an RTB pref isn't another way to start a function.
if($OAA:AdminLevel && !%client.isAdmin)
return;
The || sign means "or" and has no place there, at all.