Massallah pertaining to eating foods which contain gelatin

Assalaamualaikum
Q1)Sweets which contain gelatin from haram animals like Cows slaughtered unislamicaly,are such sweets halal?
Q2) Sweets which contain gelatin from haram animals like Pigs,because of tabdeel e mahiyat in the gelatin (made out of Pigs), will the sweets be halal?
Q3)Food colour cochineal which is made from insects, is used in a wide variety of foods will it be permissible to consume food which contain cochineal?
Q4)If food containing cochineal is halal to eat, plaese give reason?