Protecting the Form was not the problem. Inserting a Check Box in the Form and then inserting an X in the Check Box where applicable was what I was seeking to do
Gavinz, you're missing my point. I know what you want to do and, as I've stated, I know you can insert a Check Box and you can make an X appear in it by going into the Check Box Form Field Options window.
But, that does NOT create a properly working Check Box. Suppose you were creating this form for others to use. Are you going to give them instructions on changing the Check Box by your method? That would look amateurish.
To get the Check Box functioning properly, you DO need to protect the form. Applying protection is the key to making the Check Box function the way it's supposed to function. If you still don't get this point, I don't know how else to explain it. Let me reiterate one more time,
you need to protect the form if you want a properly functioning check box. If you're willling to accept an amateurish work-around approach by using your method, then that's your choice.