We have been in Morocco, briefly, last year. I know
nothing about customs as we were with a University
group. Passports were kept by the purser, customs
checked our passports before we were cleared to leave,
and we got off the ship and then back on the ship
several days later with no hassle at any point. As we
took a University sponsored field trip, the group
leader kept the passports with him at all times.
As for dress, we were cautioned to dress modestly, arms and legs covered. The students wore pants and the adults did so as well, but I wore a longish skirt. We were also cautioned about eating there as well as in various other countries. No dairy, nothing unpeeled, nothing that was cooked that was supposed to be hot and was not hot, and only bottled water.
Perhaps this was too cautionary, but for 100 days of traveling, we followed all the suggestions of our onboard physician and managed to not be sick at any time. Others who varied from the suggestions did not always fare as well, unfortunately. We ate at the assigned plces and not at stalls along the streets. I am sure your study group will have such suggestions as well.
Dry hand wash was very popular. We found two working cyber cafes and none of the hotels had public telephones. In Casablanca our taxi driver stayed with us and helped us through the unusual keyboard difficulties. Beware of hazards like removed manholes or other potential disasters when walking after dark.
One other thing is that people do not like to be photographed, so be sure to ask before you take pictures. Some will oblige and you may need to pay for the picture taking. We used dollar bills for this purpose.
All this aside, we found Morocco picturesque, the medinas fascinating, the people interesting, and would like to return again some time.
Some of the large group traveled independently and had grand times riding the trains to different cities, camping in the desert, and/or riding camels to the edge of the Sahara, staying within the boundaries of Morocco.