How to get hector_quadrotor to fly autonomously

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So, still new to ROS and the debugging of the programs. I'm trying to make a program where hector_quadrotor flies up into the air, hovers, spins, and then continues to hover before going to the next task. I've gotten it to work with just forcing the functions through:

#include <ros/ros.h>
#include <geometry_msgs/Twist.h>
#include <sensor_msgs/Range.h>
#include <sensor_msgs/LaserScan.h>
#include <sensor_msgs/Imu.h>

// tf Subscriber
#include <tf/tfMessage.h>
#include <tf/transform_listener.h>
#include <tf/transform_listener.h>
#include <tf/transform_broadcaster.h>
#include <tf/message_filter.h>
#include <message_filters/subscriber.h>

// IOStream for Testing
#include <iostream>

namespace quad_lift_spin {// Structure of Elements

// initialization of global varibles

int mapYSize = 0, mapXSize = 0, numAgents, agentID;
float agentLocation[3] = { 0, 0, 0 };

geometry_msgs::Twist lift_msg;
}

using namespace quad_lift_spin;

void quad_lift()
{
    lift_msg.linear.x = 0;
    lift_msg.linear.y = 0;
    lift_msg.linear.z = 0;
    lift_msg.angular.x = 0;
    lift_msg.angular.y = 0;
    lift_msg.angular.z = 0;

    lift_msg.linear.z = 0.5;
    ros::Duration(2).sleep(); //wait 2 seconds
    //quadLSPub.publish(lift_msg);
    /*lift_msg.linear.z = 0;
    ros::Duration(4).sleep(); //wait 4 seconds
    //quadLSPub.publish(lift_msg);*/
}

void quad_hover()
{
    lift_msg.linear.x = 0;
    lift_msg.linear.y = 0;
    lift_msg.linear.z = 0;
    lift_msg.angular.x = 0;
    lift_msg.angular.y = 0;
    lift_msg.angular.z = 0;

    /*lift_msg.linear.z = 0.5;
    ros::Duration(2).sleep(); //wait 2 seconds
    //quadLSPub.publish(lift_msg);*/
    //lift_msg.linear.z = 0;
    //ros::Duration(4).sleep(); //wait 4 seconds
    //quadLSPub.publish(lift_msg);
}

void quad_spin()
{
    lift_msg.linear.x = 0;
    lift_msg.linear.y = 0;
    lift_msg.linear.z = 0;
    lift_msg.angular.x = 0;
    lift_msg.angular.y = 0;
    lift_msg.angular.z = 0;

    lift_msg.angular.z = 0.5;
    ros::Duration(2).sleep(); //wait 2 seconds
    //quadLSPub.publish(lift_msg);

    /*lift_msg.angular.z = 0;
    ros::Duration(4).sleep(); //wait 4 seconds
    //quadLSPub.publish(lift_msg);*/
}

int main(int argc, char **argv)
{
    ros::init(argc, argv, "quad_lift_spin");
    ros::NodeHandle nh;
    //ros::NodeHandle pnh("~");

    ros::Publisher quadLSPub = nh.advertise<geometry_msgs::Twist>("cmd_vel", 10);

    quad_lift();    
    quadLSPub.publish(lift_msg);
    ros::Duration(2).sleep();
    quad_hover();
    quadLSPub.publish(lift_msg);
    ros::Duration(3).sleep();
    quad_spin();
    quadLSPub.publish(lift_msg);
    ros::Duration(5).sleep();
    quad_hover();
    quadLSPub.publish(lift_msg);
}

With this working, I've been trying to figure out the publishers and subscribers needed to get the separate functions to work and have run into a snag with the publishing and subscribing:

#include <ros/ros.h>
#include <geometry_msgs/Twist.h>
#include <sensor_msgs/Range.h>
#include <sensor_msgs/LaserScan.h>
#include <sensor_msgs/Imu.h>
#include <std_msgs/Bool.h>
#include <std_msgs/Header.h>
#include "target_alert/alert.h"

// tf Subscriber
#include <tf/tfMessage.h>
#include <tf/transform_listener.h>
#include <tf/transform_broadcaster.h>
#include <tf/message_filter.h>
#include <message_filters/subscriber.h>

// IOStream for Testing
#include <iostream>

namespace quad_lift_spin {// Structure of Elements

// initialization of global varibles

int mapYSize = 0, mapXSize = 0, numAgents, agentID;
float agentLocation[3] = { 0, 0, 0 };

geometry_msgs::Twist lift_msg;

sensor_msgs::Range sonar_height;

int flight_mode;

}

using namespace quad_lift_spin;

void quad_lift(const sensor_msgs::Range::ConstPtr &msg)
{
    lift_msg.linear.x = 0;
    lift_msg.linear.y = 0;
    lift_msg.linear.z = 0;
    lift_msg.angular.x = 0;
    lift_msg.angular.y = 0 ...