Ronaldo, 33, joined the Serie A champions from Real Madrid in a record 100 million euro transfer after nine glittering years with the European champions.
However, he's yet to open his account in Italy, after the 3-2 win over Chievo and the 2-0 victory over Lazio at the Allianz Stadium.
Ronaldo has now had more shots (14) without scoring than any other player in Europe's top five leagues this season.
"It was a different game to Verona [a 3-2 win at Chievo on the opening day]," Allegri told Sky Sport Italia.
"At first, we played in a hurry. There was a danger of getting carried away with the enthusiasm of Cristiano Ronaldo's first home match. We had to be patient.
"But I'm happy with how the players did. It was an important match, the first match against a direct rival.
"We need to work and improve. But we have Cancelo, who is a new player, Bonucci returned after a year, Ronaldo, a new player, that's 30 per cent of the team. It takes time."
"Italian football is completely different to Spanish football. Ronaldo understands that and he is settling in very well. He's a very humble guy and I'm very pleased with the impact he has made so far."