Undefined variable (with fix)

You have a undefined variable notice in your plugin at line 150.

150:
$rules_BY_id = $this->get_sub_array($options['rules'],'role',$current_user->ID);

Were $current_user is only getting set if the $user_id is null. That function should get the global removed and set a top the function.

if ($user_id == null){
	get_currentuserinfo();
	$user_id = $current_user->ID;
	if ($user_id <= 0)
		return true;
}

Also note the uppercase ID as id is deprecated.

So the function should look like:

public function limitUser($user_id = null,$type = null,$use_m = true){
	global $current_user;

http://ww.wp.xz.cn/extend/plugins/bainternet-posts-creation-limits/