Her best bet is to return to FLA. Get her CCW and buy her snubbie after the permit comes. This will give a legal right to carry in 32 states LEGALY. My other advise would be for BOTH of you to look at this web site.
http://www.handgunlaw.us/
If she is planing a trip to Maine driving there is going to be IMPOSSIBLE to do LEGALY. She has to get through MD. N.J. N.Y. CT. MA. and Maine does not honor Florida's CCW permit.
For her peace of mind she may want to re-think the snubbie for traveling. Three working day wait without CCW permit
Most states do not require a permit to keep a handgun in a person's own home. Her RV would be considered her residence and the laws for possession in a residence would apply, not the carrying laws, unless she carried it outside her RV. It sounds like possession by a resident in their own home and carrying in public or in a vehicle are being confused.