Laws which do not apply to Pesach of the Generations
Leaven was prohibited for One Day and Night: Pesachim 28b, 96a, 96a-96b
How they did the Sprinkling of Blood and Burning on the Altar: Pesachim 96a
Blood was sprinkled on the Lintel and doorposts, with a hyssop branch: Pesachim 96a
Whether the hyssop branch was bound up: Succah 11b, 33a
The Offering was consumed hastily: Pesachim 96a
The Offering was set aside on the Tenth of Nisan: Pesachim 96a
The Doorposts and Mantle [Lintel?] as witnesses to Gd's acquisition of the Jews as avadim: Kiddushin 22b
Laws which may have continued beyond that year
Eating it "Na" - partially cooked: Pesachim 96a
Prohibition against consumption by an Uncircumcised Male and an Intentional Transgressor: Pesachim 96a
Consumption by a Eved Ivri: Pesachim 96a
One who has household members or salves who are not circumcised: Pesachim 96a
The Departure
The taste of the Manna in the loaves which they brought out of Egypt: Kiddushin 38a