The Rule to Show Cause only applies to whether or not the party should be held in contempt for violating the order. If you want to modify the original order based on a substantial change in circumstances, you'll have to file a complaint.
Please be advised that this comment should in no way be interpreted as legal advice, nor should one rely on this comment in making a final decision about his or her case. Each case is fact specific and peculiar in its own way. Thus, you should consult with an attorney in-person or over the phone, explaining your particular situation, so that the attorney can render fully effective and competent assistance tailored to your particular situation.
If you have joint parenting and want to modify any part of that prior order you must petition the court for a modification of your custody. You will most likely need to hire an attorney to help you with this.
Your question does not include enough information regarding your child custody case to provide you with a substantive response. Additionally, you post consists primarily of multiple questions without much supporting explanation/facts. You should consult an attorney in your jurisdiction about your case specifics; I would advise you do so quickly where you express a concern that he may leave the state. Best of luck.
This is not legal advice. This response is provided for general information only, as a public service. It is not to be relied upon as legal advice and does not create an attorney/client relationship; nor is it an attempt to create an attorney/client relationship. Consult with local counsel in your jurisdiction about the specifics of your case, which is the only way to gain true meaningful legal guidance and/or representation.