i have architected myself a flyertalk worthy travel home for the holidays itinerary, consisting of 2 PNRs and 4 flights.

ATH-FCO-TUN on ita airways arriving 10:35
TUN-AMM-ORD on royal jordanian departing 14:35

is there anything i need to know about transiting tunis? i have a carry on sized bag that i usually check in. should i try to stick with it as a carry on ATH-FCO-TUN then check it in via a transit gate in TUN? will i be able to do this, or will i have to arrive in TUN anyway? i assume not but am unfamiliar with the country/airport and how things may go down, so advice appreciated!